Your question is indeed too generic, but there are some guidelines you should keep in mind to help you make good decisions after the opening and "standard" development of pieces has ended. It is very important that you should try to understand the position, in terms of:
1. king's safety Basically, if your king is exposed (you haven't castled yet, or the pawn structure defending your king is not the way it is supposed to be) you should think of ways to make it more secure. Furthermore, if your opponent's king is vulnerable for the same reasons stated above, you shoud try to make energic, threatening moves, so he doesn't have the necessary time to secure it.
2.Pawn structure Regarding the pawn structure you should identify the weak pawns (yours and your opponent's, ofc) and the weak squares (sqaures that cannot be defended by a pawn). You should, by all means, avoid damaging your structure and try to exploit your opponent's weaknesses.
3.Good pieces, bad pieces After the development of the pieces is over, there will almost certainly be pieces that can find a better square where they should get. The good pieces dictate the plan to regroup the bad pieces so that finally, they will cooperate for the same strategic reasons. In case bad pieces cannot be repositioned, you should try to exchange them as soon as possible.
4.Center and space The most important part of the chess table, where all the actions revolves around is the center. You should try to occupy it and control it with most of your forces and also gain some space advantage by means of advancing pawns (space advantage is,in fact, the second most important positional advantage in chess, besides king's safety)
That being sad, the principles stated above can be applied in the position you are reffering to, in the following ways:
1.Both the kings are safe, so there is no reason to make defensive moves or generate chaos in order to stop black from defending his king.
2.Although the pawn structure is symmetrical (both sides have one pawn for each column), notice the "loose" pawn on h5. One plan could be to try and attack this pawn by means of Bd3 but as you will see, black easily defends it by g7-g6.
3.White's development went nicely, so there are no bad pieces on his side. Maybe the bishop on c3 is pretty misplaced, due to the fact that it is blocking the c2 pawn, which could advance to c4 and threaten black's center. Black is quite ok also, but notice his bishop on c8. It is still on his initial square thus preventing the rooks from communicating via 8th line. Also, there is no good square for this bishop, as black's center pawns are blocked on white squares, limitating the c8 bishop's activity. Very important to observe here is that white posesses the pair of bishops, which is a deadly weapon in open positions. So we must open the center and exchange a couple of pawns to open this position.
4.As of space advantage, neither side has any. We may say black is a little better from this point of view due to the advanced pawn on h5, but being so marginally, it doesn't help much. Regarding the center, white has a little advantage. His extra black bishop help control the e5 square, a critical square in this position.
So, if you put the pieces together, and remember what you must do, you will get to the right moves and plans. For example:
a) White has to prepare the advance of the c-pawn.
b) White has to open the position for his pair of bishops
That being sad, the right plan is : b2-b3 followed by Bc3-b2 and c2-c4 (maybe Ra1-c1 before, but not necessarily)
I hope I made a good point, as this is my first post on 2+2. Hello, fellow Poker&Chess Players