How do I stop defending and start attacking?
here are some comments on your game as black, again dont take my word for them as i'm quite a bad player
First off, doing tactics is a big help and making sure not to lose pieces carelessly. Doing that makes it very difficult to attack. If you want a quick lesson on attacking in the early bits of the game which is quite fun sometimes, you should probably avoid all the moves like a3, d3, h3, and g3 for more ambitious center-fighting pawn moves or other developing moves. From there, attacks sometimes just come naturally. Obviously you can't realistically attack every game but that should start you off better.
First game -move 5. a3 is a so so move, its like giving the momentum to black. I don't consider it a developing move. It is a defensive move. Perhaps another move to develop a stronger center. ?pawn to d3. check with your sw. Castling on the q side, IMHO, may cause a loss of a move at some point, you might have to move your K to b1. So I don't do it unless it gives me some type of advantage. Good luck.
its definetly better than h6, and when black weakens himself and also wastes a move i dont think that one so so move will turn over the momentum
First off, doing tactics is a big help and making sure not to lose pieces carelessly. Doing that makes it very difficult to attack. If you want a quick lesson on attacking in the early bits of the game which is quite fun sometimes, you should probably avoid all the moves like a3, d3, h3, and g3 for more ambitious center-fighting pawn moves or other developing moves. From there, attacks sometimes just come naturally. Obviously you can't realistically attack every game but that should start you off better.
well you can with white i guess

Game 1: Nc3 and a3 are duds. After ...h6 (a horrible, lame move), a swift d4 is called for. A few moves later you play another defensive move: h3.
These lost the initiative for your game. When you start playing defensive moves, you aren't attacking. And it's you who put you on the defensive, not your opponent.
Game 2: move 2...Nc6 is a klunk. You need to have a potential c5 to use as a lever against White's pawn center. 6... Bd6 was not such a bad move, it was played to stop the double attack on the backward c7 pawn. If white takes, you can take cxd6 and then you have more support to play an eventual e5 break against the d-pawn. You didn't like your move 13. Look at the position with the pawn on c5 and think of my first point about move 2.
The opening is generally a battle for the initiative and control of the center. In both games, you did not use crucial moments to improve your position and punch at your opponent's center, even after a couple of dud moves by your opponent, who also failed to play particularly aggressively.
Something that helped my games and may help yours is the "flip board" feature on this site. After I have selected my "candidate moves," I flip the board and consider the opponent's response, as well as the strength and weakness in his position. This approach has slowed down my play and increased my board awareness which, coup[led with my drill in tactics recognition has yielded positive results in my game. Good luck.

I don't know how to begin to thank ALL OF YOU for your input on this thread. I really believe I now have a better idea of what things doing wrong and what I should do about them. Thanks, everyone!

In your first game when the black bishop move to: 8 .... Bh4,
You could have won a piece if your white Bishop would have taken the pawn
9. BxF7+ KxF7. 10. KtxE5+ KtxE5 11. Qxh5+ G6 12. Qxh4
Now you have lost the white bishop and a knight.
You won two pawns a knight and a bishop and he can't castle
He can swap queens and you are slightly ahead but at least you became aggresive and attacked.
In you games you seem to give away pieces for less compensation.
You gave away the bishop when you had to take the f7 pawn and the a rook later on near the end of the game.
Look for small combinations where you don't lose pieces but make equal trades.
IMHO.

PS:
Castle early don't wait until you have to. Twice you castled Queens side.
I have my players castle in the first five move.

And thanks for the last post too! I had not realized that castling queenside was considered inferior to castling kingside. I have learned a great deal from this thread. I have never considered what color square my lone bishop is on when I moved my pawns, but I shall in future. I shall also pay more attention to trying to control the center, and not making a defensive move if I can attack instead. And I think Dr. Spudnik was correct when he said that it is not my opponent who puts me on the defensive. I have a lot to learn, but I shall soldier on, and I do hope the wonderful advice in this thread helps a few other weak players too. Thanks again to everyone who took the time to study my games.
I think it would be a good idea for you to learn some theory. Many say that's not important at your rating, but it would really help you to know something about what you are "supposed" to do. The whole opening phase of the game where you played White is filled with pointless moves like a3, ...h6 and so on.
In that game Black was clearly afraid of the double attack on f7 after 4. Ng5. That is why he played 3. ...h6. This is not necessary. After 3. ...Nf6 4. Ng5 Black plays 4. ...d5! 5. exd5 Na5 with one of the most well known positions in chess history.
You should get an introductory book on the Italian game (that's the name of the opening after White's 3rd move). I promise you that you will learn much and that you will never regret spending some chess-time on that opening. You will learn classical development and tactical themes that will help you in all other openings as well.

Dozeoff,
Yes, I knew I was beginning with the first few moves of the Italian Game, but I have not had a chance to study it properly. I generally only use the first few moves and then "wing it", because people at my level do not respond according to book. I just enjoy using those first moves anyway. Suppose I were to study a book on the Italian Game ... would it cover how I should proceed when my opponent is simply playing some other game? By the way, thanks for your comments.

You don't need to learn specific lines, just be aware of what advantages and disadvantages your opening has, and some ideas on how to make use of your advantages.
Try to set up counter-threats when you can. If your every move is defensive, your opponent can develop the attack at leisure, and you are placing a large burden on your tactical ability to thwart the attack. But if you give your opponent something to think about, some threat or potential threat (it could be as simple as putting an unbusied rook on an open file), it takes a lot of pressure off of your defense and gives you a chance to take the initiative.

Thanks Ivandh, more good advice. I like the idea of giving my opponent something to think about. Sometimes I suspect he nods off during our games!
In so many of my games, I seem to be put on the defensive early on, and end up being driven back into a small area of the board, from which I can never break out. I never seem to be able to attack this particular opponent. Can someone help me to see what it is that I'm doing wrong? In the first game I play white.
In this next game I play black.