Spotting a bottom in stock prices when the market goes through a selloff is tough business. The major averages posted losses for the second day in a row Wednesday with the Dow Jones Industrial Average declining more than 43 points, the dipping 0.20% and the Nasdaq Composite dropping 0.38%. Stocks rallied Monday after President Donald Trump halted tariffs on Mexican imports, but have sunk since. CNBC's Jim Cramer said Wednesday that there are three clues to track a trough: the company's estimates, stock action and the wit of other shareholders. "You typically don't get a real bottom until the estimate cuts have been made, the stocks been softened up, and the clueless hot money has abandoned it," the "Mad Money" host said. "That's a bottom. Anything less than that, and you're probably too early, which means you're going to get hurt." Cramer took a look at a few stocks to explain the difference between "value and a value trap."

FedEx

Credit Suisse, citing "temporary volume" and "cost headwinds," recently chopped its price target for FedEx to $184 from $241. Still, the transport stock gained nearly $2 per share during Wednesday's session, Cramer said. FedEx stock had dropped from about $199 per share in April to lows near $150 early last week. Since then the equity traded as low as $164 before settling at $161.37 Wednesday. Cramer said investors can take the downgrade and "file it away," meaning the "worst may be over" for FedEx. He thinks the stock is about to bounce on bad news. "If an analyst is cutting numbers and that cut can't knock the stock down, that means you won't get hurt," he said. "If you believe the President can work out a deal with China ... this is the one to buy ... And if the trade war continues? Well, I have to start thinking that the bad news after this piece today is baked in, and that is fabulous."

Salesforce

Salesforce saw its stock plummet from about $161 per share to roughly $152 after announcing Monday it would buy Tableau Software for more than $15 billion in an all-stock deal. The stock saw a similar downtrend after the customer relations management cloud company bought Mulesoft in 2018, Cramer noted. Salesforce's shares tumbled on news of that acquisition as well and roared back weeks later, he said. The host called the most recent selloff "pretty extreme, especially after the company reported a terrific quarter just a few days before." "I think you may end up looking at this latest, single merger-induced pullback and say ... 'I think the worst is over. I think that the stock up today means buy, buy, buy,'" Cramer said. "Now, maybe it's too soon to buy this one ... With Salesforce up $1.13 today, it sure does look interesting. I'm endorsing it half position now, half position later."

Facebook

Cramer warned to be careful with "sentiment-based" bottom calls. In the case of Facebook, Cramer thought all the bad news about the internet giant's privacy practices had already been baked into the stock price. But the latest negative headline Wednesday that suggested CEO Mark Zuckerberg could be personally linked to questionable privacy issues dented the stock. "I read that, and I thought I was reading an old headline. I mean, something that had run multiple times," Cramer said. "People didn't regard it as 'same old, same old.' ... Incredibly, this story has legs." Facebook's shares dropped more than $3 per share during Wednesday's session. "One of these days, Facebook's stock is going to stop going down on this kind of story," Cramer said. "Now, I think it's actually worth buying here, as long as you build your position gradually and add more if the stock gets hit."

WATCH: Cramer speaks on spotting a market bottom