Buy on weakness. Buy on a pullback. Buy when it goes lower. These are all things you've heard Jim Cramer say repeatedly on Mad Money, and that's so you'll be ready for days like today.

Cramer said he could tell the markets were in for a lower opening after Unilever (UL) reported a big miss and Apple (AAPL) was forecast lower. On the anniversary of the 1987 market crash, profit taking was more than likely in a big up market. And that's precisely the time when you open up your playbook and have your shopping list ready.

Cramer said he first looked to IBM (IBM) after a great interview on last's night's show, but IBM shares weren't going to pull back. He next looked at Adobe Systems (ADBE) , which just posted a better-than-expected quarter, but no luck there, either. Same with Johnson & Johnson (JNJ) .

With all those companies eliminated, Cramer said he next looked for companies that still had good earnings, but maybe weren't as recent as his first group. Allergan (AGN) , Abbott Labs (ABT) and United Airlines (UAL) made the list, but he decided against those as well.

Cramer finally settled on Alphabet (GOOGL) , which was down despite announcing a $1 billion investment in Uber competitor, Lyft. He also decided on LAM Research (LRCX) , which was also lower despite a great long-term story.

Every investor should have their battle plan ready, Cramer concluded, because when the markets open lower on trivial things like anniversaries, that's the time to pounce. Nobody ever made a dime panicking.

Over on Real Money, Cramer says he's looking for stocks that just gave us terrific information about how they are doing and that are away from the European and Chinese blast zones. Get his insights with a free trial subscription to Real Money.

Executive Decision: Skyworks 

For his "Executive Decision" segment, Cramer welcomed back Liam Griffin, president and CEO of Skyworks Solutions (SWKS) , a stock that's up 38% for the year, but also one that fell 3.7% today as the broader averages sank.

Griffin explained that the mobile internet economy is here to stay and isn't going away. All of the top technologies companies are focused on mobile, and for good reason. In countries like China, mobile is everything, and Skyworks is a catalyst that makes mobile happen.

Griffin was most excited about the upcoming 5G wireless transition. 5G, he said, will be a whole new network on all-new spectrum that will boast speeds between three and six gigabytes. It will clear the digital logjam we have today and every one of the 5.5 billion smartphone users out there today will eventually upgrade to it.

As for his company's operating performance, Griffin noted that between 2013 and 2107, Skyworks was able to more than double their revenues and increase operating margins to near 40%. His company builds its chips in Boston, Los Angeles, China, Mexico and Singapore, Griffin said, bringing together all of the best technologies in the world.

Cramer and the AAP team are trimming some Southwest (LUV) shares to lock in a strong gain. Find out what they're telling their investment club members and get in on the conversation with a free trial subscription to Action Alerts PLUS.

Lessons From the Black Monday Crash 

They say it's better to be lucky than good. But it's even better to be lucky and good, Cramer told viewers, as he recalled the events of Black Monday. That was 30 years ago today, when 20% of the market's value disappeared in a single day. He said that while everyone remembers that Monday, it was the next day, Tuesday, that was the most scary.

That's because Tuesday, the market simply failed. Our screens didn't work, Cramer said, and no one knew what the price of anything was. Were shares of Caterpillar (CAT) at $50 or $65? Not even the market specialists could tell you.

Making matters worse, Cramer said despite liquidating his entire portfolio just days earlier on a hot tip from Karen Cramer, when he looked at his account balance, there was no money in it. Clearing houses had no cash and there were fears that they might not ever have the cash. Fortunately, then-Federal Reserve chair Alan Greenspan was offering liquidity, but even then it took over a week for funds to arrive.

So while the machines do rule Wall Street today, investors should take some comfort that there are circuit breakers and limits that keep the markets -- for the most part -- orderly, and the flow of information is such that just about everyone has an idea of what's really happening.

Read more about the crash of '87 in TheStreet's special report:

Executive Decision: Winnebago Industries 

In his second "Executive Decision" segment, Cramer also spoke with Michael Happe, president and CEO of Winnebago Industries Inc.  (WGO) , a stock that's up 44% this year, thanks in part to today's nine-cents-a-share earnings beat with revenues that were up 73% year-over-year. Winnebago also announced a $70 million stock buyback, equivalent to 5% of the company's market cap. Shares closed up 3% on the news.

Happy explained that Winnebago is on a high-growth trajectory and is very busy expanding capacity to meet future demand. Winnebago was one of the pioneers of the RV market, but the race to get outdoors and create new experiences still runs strong.

In November of 2016, Winnebago acquired Grand Design, makers of towable RVs and Happe said the acquisition has been an excellent combination of talent and passion, and Grand Design is producing innovative products at a very fast pace.

When asked about those new products, Happe said that nearly 80% of all RV owners want to be off the grid but still connected to the world so that they can share their experiences, which is why many of their offerings now include all the connectivity of home no matter where you might be.

Lightning Round

In the Lightning Round, Cramer was bullish on Activision Blizzard (ATVI) , Enterprise Products Partners (EPD) , Ventas (VTR) , Xilinx (XLNX) , PayPal (PYPL) , Mastercard (MA) , Visa (V) , Tower Semiconductor (TSEM) , Priceline Group (PCLN) and USG Corp (USG) .

Cramer was bearish on International Game Technology (IGT) , Omega Healthcare (OHI) and Global Payments (GPN) .

Am I Diversified?

In the "Am I Diversified" segment, Cramer spoke with callers and responded to tweets sent via Twitter to @JimCramer to see if investors' portfolios have what it takes for today's markets.

The first portfolio included Xylem (XYL) , FMC (FMC) , McCormick (MKC) , Raytheon (RTN) and Allergan (AGN) .

Cramer said this portfolio was properly diversified.

The second portfolio's top holdings included Adobe Systems (ADBE) , Facebook (FB) , Mazor Robotics (MZOR) , DowDuPont (DWDP) and Square (SQ) .

Cramer said while this portfolio was diversified, it's also a little on the risky side.

The third portfolio had Canadian Pacific (CP) , Scorpio Tankers (STNK) , HP (HPQ) , Alcoa (AA) and Ternium (TX) . as its top five stocks.

Cramer said Alcoa and Ternium were too similar and this portfolio needed Abbott Labs (ABT) to replace one of them.

Finally, the last portfolio's top stocks were Apple (AAPL) , Microsoft (WBA) , Bank of America (BAC) , Microsoft (MSFT) and AT&T (T) .

Cramer said this portfolio can't have both Apple and Microsoft and he suggested adding Honeywell (HON) in place of Microsoft.

You're Invited

Cramer will host CNBC's Jon Najarian, TD Ameritrade's JJ Kinahan, famed analytics expert Marc Chaikin and other market experts on Oct. 28 in New York City to share successful strategies for active investors.

You can join them as they discuss how smart investors can make the most of options trading, futures contracts, fundamental and quantitative analysis and great ETFs to buy right now. Participants will also get a chance to meet Jim and other panelists.

When: Saturday, Oct. 28, 8 a.m. to 3 p.m.; Where: The Harvard Club of New York, 35 West 44th St., New York; Cost: $250 per person. Click here for the full conference agenda or to reserve your seat now.

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At the time of publication, Cramer's Action Alerts PLUS had a position in LUV, AGN, ABT, GOOGL, AAPL, ATVI, FB, DWDP.

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