When you are serve returning you need to be careful where you stand. Most players stand in the backhand side just because everyone else does. But really you should be diagonal of where your opponent is standing, because they are most likely to serve it cross court. Another thing people seem to have a problem with is getting jammed because they stand close to the table. A good rule of thumb when serve returning is if you can touch the table with your racket, you are probably too close.
While serving there is really one main thing you need to do between your serve and next shot. It really doesn’t matter where or what you serve, but go directly diagonal from your shot. I would say about 6-7 out of 10 times, your opponent will return your serve cross court, so going across from your serve will be the most logical thing to do.
With making these two small changes to your table tennis game, I believe it can help tremendously with your game.