Ok, here we go...
Full skidplates, A-arms, swingarm, main part of the frame. <Pretty much mandatory
Lower gearing, 20-22" rear tires, Handguards, Nerf Bars, Better Shocks front and rear for sure, depending on how wide the trails are that you ride on, you may want to invest in a wider axle and extended a-arms, G-Force makes an axle that has an adjustable width, pretty handy. The cheap way out would be wheel spacers, but its the cheap way, you get what you pay for. Bar risers if you're over 5'10" Gripper seat cover, 1-2" extended swingarm if you need it. I find that i don't. If you are riding at night upgrade your lights, either with the wally world lights or an HID conversion on the stocker.
Also, ride with a backpack with some tools and spark plugs and stuff like that, It sucks to be stranded with a fouled plug.