1. Eradicated blunders from your game. Activate move confirmation in your profile. Think about your moven play it, check it is no blunder, confirm it.
2. Play slower. In a 15+15 time control you should use all your time by move 30 and then finish the game on increment.
3. Tactics: tactics of your own, tactics of you ropponent.
Example
You were doing OK, but the whole diversion 9 Be5, 12 Nb3, 14 Nc5, 15 Na6 is wrong. Play the center, not the wings. 9 Ne5 12 Re114 Bf4 15 Nd3 were more indicated.
17 Qa4 loses a vital pawn and leaves your king in peril. 17 Kg2 was needed.
18 Qxc6 is reckless 18 Kh2 was needed
19 Qxb7 runs into direct checkmate
At the very end of this 15+15 time control game you have 13 useless minutes left on your clock. You had better invested these minutes to find the right plan and/otr to find more accurate moves.