Sicilian defence

I don't know why but when white plays bishop to c4 on the 3rd or 4th move I always have trouble. What is a good reply?

Play ...e6 to blunt the bishop's effect on the c4-f7 diagonal.  Then you might try to chase the bishop with ...a6...b5.  I have had success with that plan.

thanks. I am trying to get good at the dragon variation where the king bishop goes to g7 but maybe that doesn't work too well with that white bishop move.

I always have my worst games against 2. Bc4. e6 then a6 with Bb7 I find works really well...

The Dragon variation is something you can play in the position after 1.e4 c5 2.Nf3 d6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3.

If White plays differently, it doesn't matter what you were going to play in that position -- it won't arise in this game! That you were going to play the Dragon is as relevant as what you were going to do against 1.d4.

(transpositions are the exception -- white could play 2.Nc3, and 3.Nf3 4.d4 only later, for instance. You might want to play moves that still allow your preferred variation, but now always. And after 3 or 4 Bc4, you have better options, so forget about the Dragon)

one of my most fav defences..