Welp. I sucked!!

1524?

Study tactics tactics tactics.

Only played 4 games (5 now) Ignore that rating.

Only had a quick run through as I'm sure you're well aware of the many errors you made.

4. a3, although unneccessary at that point, it does prevent in the future the dark bishop or knight from utilising the b4 square to attack your king or c2 pawn. However given your opening, the more flank pawns you push, the less cover your king has when you come to castle, ideally in most positions you'd like a 3 pawn defence, perhaps with a fianchettod bishop even. a or h pawn pushes early on give the opponent a nice area to attack, especially if they can get a rook or queen to pin the b or g pawn to a castled king

However, it did start to go downhill from move 6, and it took 10 moves before you moved a knight, by which point your opponent had lined several pieces on the border of your half of the board.

From then on it was obvious you wouldn't have chance to castle with your light bishop trapped, and blacks queen on the other side. You best chance would have been to repel the enemy pieces. Perhaps 12. g4, either eventually forcing the bishop to d7, rendering it useless and blocking the rook, or they blunder it on to the g6 square or do a poor sac. Then you could get your bishop involved and perhaps look to remove that decent d5 knight.  You won't have any cover left for the king and its still a bad position to be in, but its better than dying a slow cramped death.

2. f4 is not really to the point. d4 would contest more central squares.

3. d3 instead of Nc3, which develops and protects a pawn.

You recognized that 4. a3 was lame and pointless. But after his 4... Nc5 you could play b4, hitting the Knight and making a place for the Bishop to develop.

5. Be3 allows Qb6 hitting the weakie on b2 (and the Rook in the corner)

Develop Knights before Bishops unless you have a distinct & clear reason to not.

7. Bxc5 trades off your only developed piece. Why not just develop the Knight to f3? Get your pieces out where they can do you some good...then start attacking weak points.

Generally, I'd say you should develop instead of taking pot shots at your opponent's pieces.

Lol :( Danny Rensch says you should always be able to castle before move 10.