The first thing you should probably do (and it would get you to 61 cards, though your mana might be a little off) is get down to a red and green deck only. (This includes dropping the three artifacts and lands that produce colors other than red or green.) They don't add enough to the deck to make it worth splashing, you don't have enough mana fixing to make it consistent in pulling them. Keeping your decks to one or two colors will greatly enhance the decks consistency, especially for newer players that don't have the fetch lands and other prime fixing needed for higher color count decks.
I'm guessing this is built off cards you actually own, so I won't list cards that will help the deck since you probably don't own them and most of them will be pricey. I'd suggest getting your land to about 23. Round out your deck from there, keeping an eye on your curve (although you don't seem to be that terrible there.)