I start her with boots and 3x health pots, but a lot of people start her with cloth. Its up to you, boots for aggressive early game, cloth for longer stay in the jungle, which I am sure you know. I feel the most effective way is boots. Picking up Merc treads after Wriggles then Wit's, somewhere inbetween those items I pick up Heart of Gold. After that it depends on what you need, tanky or dps. If unsure pick up Frozen Mallet. Summoner spells I use are Exhaust and Smite.
Max burnout asap pick it up at lvl 1. Pick up twin bite at lvl 2 and max at 13.
No comment on Varus, havn't seen enough of him yet.