help finishing?

When you have a big advantage like this, you should try to trade off pieces. If you can get down to your queen vs. his rook, you'll be winning easily. Leaving more pieces on the board can complicate things for you (like in this game).  You also let his pawns cramp your king, and gave his knight a big protected hole on f3. No specific comments right now, but hopefully this helps a bit.  For example, instead of 18. e5, try 18. Bb5, pinning the knight to the rook. If he plays a6, just play Bxc6. You'll double his pawns and move closer to a won endgame. Remember, there's no shame in trading off material when it guarantees a win.

biarien couldnt have said it better 18.Bb5 is of course the most accurate move

To add to the above, you should try to avoid opening up a nice file for his Rook to dominate.  After you were up material you threw away a your central controlling pawns which allowed his Rooks into the game.  When you are up material to this extent you should look to limit the movement of his pieces as much as possible and trade off where possible, not open up angles for him to counter-attack.  You don't need to take risks in this position, and you don't need to rush your advance of pawns; he is the one who needs to do a lot of thinking to work out how he can get into the game.  Your Queen has far more mobility to navigate through a closed central position than his Rooks.

Finally, never assume a game is won until you have won it; just because you are winning doesn't mean you can afford (justifiably) to throw away a pawn here or there.  Play as if it is still all to play for and you won't be disapointed.

Hope this helps!

A 

solid thanks for the help guys