Sometimes play into an opponent's strength
Something that needs re-emphasis - if something your opponent does give you trouble (other than serves), play into it until you are comfortable with it. Then, just when the opponent has gotten comfortable doing this thing, avoid it like the plague. He'll still probably get to use it, but now you'll be comfortable against it, and he'll have to adjust his whole game in mid-match to find ways to use it. How many times have you come off a table with a loss still feeling uncomfortable against whatever it was your opponent was doing and feeling like you have no answer for it? That should never happen in any match that is remotely competitive.
A classic example is playing someone with short pips on the backhand. If you have trouble with the short pips, play into it until you are comfortable.
Why you choke