26% AS / 8.5 AD runes

First Blood
Early game: Smite the gromp/krugs, you should be level 2, then invade the enemy jungler (he should be doing his red/blue buff). If they started on the blue side, walk up to the bush next to the red buff, and from then on you will have to try and get first blood. Sometimes it'll be better to land an auto attack first, and Q him as late as possible, sometimes it's vice-versa.
Note: In 99% of the cases you will have to sacrifice your flash to secure this kill.

If they're on the red/purple side doing blue buff, they WILL see you walking up to them (unless they have absolutely no awareness), but it's still possible to get a kill out of this. You could also try to walk around the blue and enter from the northern passage.

Build tip: Always buy about 2 health pots to be able to sustain in the jungle. When you finished building the vampiric scepter for your BT you won't need the pots anymore.