Here are some tips off the top of my head:
(1) Both sides want to play P-Q4 in this position. White can do this before Black, so Black usually prepares for this with ...e6 first, to support his upcoming ...d5. Most players prefer *not* to lock up the e-pawns with e4, ...e5 followed by d3 and ...d6, though it's playable, just annoying and complicated.
(2) Black should play ...O-O before opening his d-file, otherwise his queen will be exposed to White's queen, which would allow Qxd8+, which would be annoying since it would force either loss of castling via ...Kxd8 or the piece retreat ...Nxd8, whereas after ...O-O the KR covers the queen without drawbacks.
(3) Black must respond to d4 with ...cxd4 immediately, otherwise (as in the Sicilian) he runs into various positional problems. White should do the same when Black plays ...d5.
(4) *Without* White's K-side fianchetto Black can usually safely play both ...d5 and ...c5 as a variation of the Queen's Gambit but *with* that fianchetto as shown, Black cannot safely make that gambit because the d5-square is covered too many times.
(5) White often plays a3 followed by b4, preceded in there somewhere by Rab1 to back up the advancing b-pawn. It is not only safe for Black to copy these moves, but that is usually the preferred response, though Black might have to be delayed 1-2 moves in doing so, for tactical reasons. The idea is to attack the c-pawns, probably to get lines open and get the game more exciting.
(6) Black can often safely copy White with perfect symmetry out to around 10 moves, if that is your style.
(7) It appears to be disadvantageous for either side to use the fianchettoed bishop in BxN, PxB, since the doubled pawns aren't disadvantageous enough to throw away such an important piece.
(8) Tactics often involve White's rook at a1 being threatened by discovered attack from Black's fianchettoed bishop at g7, or vice versa.
(9) It is common and usually surprisingly safe to play ...Be6 even when it places that bishop in front of the unadvanced e-pawn.
(10) The position tends to be very drawish, especially with any follow-up symmetry, so both players should be careful not to play too hard for a win, lest they get into a losing position.
I'm still in a testing phase and haven't found one opening which i'm super comfortable to play. Before semi slav i tried the benko. I loved the theme of it but i lost to many blitz games making me think that i don't grasp the opening enough. I might go back to it... 
Hi all,
I was called last minute for an team OTB match (slow time control) this sunday and i'm going to play black. It's a first for me!
I do have a "repertoire" (if you can call that a repertoire) against d4 (semi slav or just early c5-cxd4, Bf4 set up against some london lines) and against e4 ( the caro kann). But i have played so rarely against the English that i haven't got anything against it. i just play the first moves of the symmetrical to land in those kind of position (see below) because i figure i can't do much wrong.
Do you have some tips on the main ideas, or lines ,for this type of structure? Thanks a lot in advance