There have been many accusations leveled against me that my articles contain embellishments, misremembrances or outright falsehoods. To those, I say, "Mom, relax--It's just a bridge column". 

Sure, a story may be stretched to make a particular point, but stretching to make a point is a key part of bridge. As you improve, you'll see that there are times when you can't perfectly describe your hand in the auction or there are times when you don't want partner to play a certain suit for your own reasons. '

How are we to separate truth from fiction, then at the bridge table, if a player can overcall a 4-card suit when it should be five or signal that they don't like a suit when they hold the ace? 

First, let's talk about the auction. In the auction, you don't want to lie UNLESS you can't tell your story in any other way. Consider one of the most frequent lies we have to make: 

 4  
 KJ2  
 AJ32  
 KJ543
 

What should we open the bidding? If we open 1, and our partner bids 1, we're going to have to lie. Either we rebid 1NT (not balanced when we should be), rebid 2 (which should be a 6-card suit), or WORST OF ALL bid 2 (which should promise this shape in the minors, but with a much better hand). Since a lie is inevitable you might choose to start by opening 1 and plan on rebidding 2. This lie distorts your minor shape, but the first rule of lying in the auction is: better to lie about minors than majors. 

The second rule of lying about the auction: better to lie when partner has already passed once. Consider third-seat openings. This is where you are free to stretch all definitions of opening bids or preempts. You can open a hand like: 

 32  
 KQJ109  
 Q876  
 43
 

In third seat I would happily open 1 or, even better 2. One is a lie about strength, one is a lie about shape, but both tell my partner that I like hearts--and that's the truth. It's also a message I might not be able to get across otherwise. I would be less inclined open a 9 or 10 points hand that had a bad heart suit. 

The third rule of lying: if partner mentions that you didn't quite have your bid, mention your failing eyesight or how you mis-sorted your hand (this worked better before so much bridge was online). 

Lastly, notice I didn't talk about either psychs or upgrades. For psychs (if you've never heard of these, don't worry), I STRONGLY recommend that you ignore the concept completely. It's not a part of bridge worth getting into. If someone does psych, it's more likely to work against them than it is to help them so don't get distracted by it. Too many people worry about this and then forget to bid their own hands.

As for upgrades--I STRONGLY recommend that you trust your hand evaluation. If you think a hand looks like a notrump opener, open 1NT. I would open notrump with a good 14-count (no you don't have to announce it, but it's probably less likely to upset anyone if you do).