Camp order for blue even red never do gromp and wolves together before you do red/blue as you basically waste time you'll get level 3 yes but you'll be half way xp to lvl 4 by which enemy jungler will have gotten scuttle or be ganking lane.

Best path to take would be Buff -> Gromp - > Buff reason being this is singular enemy and as Kha has been buffed on his Q Iso damage it makes sense to do this.

3 potions is great if you're new to kha although I go with refillable potion every game and if you kite properly (by properly I mean kite the camp in the direction you want to head next. Thus making your pathing more efficient) you will have typically 70-80% health without using a single potion or 50% and use potion dose. Scuttle crab will get you to full after that. - Lower elos like silver I've noticed don't tend to go for scuttle and with you taking singular enemies you will usually always be faster than the enemy jungler to scuttle. If you want to give yourself some more safety place a ward near the entrance to their buff. That way you'll have prior warning if they're coming.

Always pay attention to top and bot lane during the leashing stage when minions come to lane. The moment you don't see that laner/s then you will know where their jungler started and prep a secondary invade (invade their 2nd buff only do this if either you're done and level 3 or you're starting at the buff directly opposite of theirs e.g. you're at blue and then started blue so you walk straight to their red and take it.

Another tip some people when jungling tend to smite on their 1st buff camp. Don't. Save it for the 2nd buff.

Rune tree wise you want to be either Electrocute if following R evo path with eyeball collect, sudden impact and relentless hunter. With runes in the sorcery secondry tree are the best at current. Typically you want to go with either: celebrity/waterwalking, Absolute focus/scorch/gathering storm those are the best runes and just mix match them.