For ganking, Frozen Mallet is your friend. It makes her tankier and actually stick to a target after you combo so you can finish what you start with Q+E.
To start, typical Machete + 5 pot is best. Take life steal quints, armor seals, MR blues, and AD marks. Take Blue first. Once you are level 3, you can pull off ganks with the help of red if you go 1pt in Q,W,and E.
Upgrade to Madred's Razors for faster clear. Boots you want are Boots of Swiftness. After you get the Frozen Mallet, you pick up Zephyr. You'll enjoy the Tenacity and move speed will be very high so just run and gank option becomes available (which saves your Q for escapes).
Team fights will be your main focus next. Pick up Warmog's because you're the tank. Your W will give you attack speed, armor reduction, and damage. So it's like having a partial cleaver (20% armor reduction), partial phantom dancer (50% AS), and more damage. So max your W before your team fight phase starts.
If the game is taking long, Bloodthirster is your next item. This gives you more damage and sustain. If the game is taking forever, sell Madred's Razors and buy a Guardian Angel.