No problem.
Okay, I'm not very familiar with Rengar wand Warwick, but I can DEFINATELY help you with Vi, as she was my main for a while.
Here's my strategy I use almost every game.
At the beginning of the game, start off with a hunter's Machete and two health potions. Level up W as your first ability. Now, if you want to take a small risk, you can go tho the enemy red/blue buff (whichever one you predict they AREN'T going to get a leash on (usually the top lane side.) (make sure you use your wards to verify they aren't there)
- as soon as you start hitting the Brambleback or Sentinel, activate one of your refillable potions. Just keep hitting it from there on. Your W passive will give you a small burst of attack speed, and you will chip away at its armor. Once your health bar drops below half, you can smite it if you wish to kill it faster and heal back up. Once you kill it and hit level two, upgrade your Q ability. (I sometimes like to use it immediately to get myself out of there in case if the enemy jungler is might be coming your way)
- I like to (as I mentioned before,) go and take Gromp/wolves right after, and to go heal up with a scuttle crab afterwards.
- If you can utilize your smite charges, second potion, scuttle crab, and honey fruits wisely, you can get to level eight or so with 1500 gold or more once you recall the first time.
^^
When doing this, make sure you can communicate to your team that you don't want them to help you, as to not attract attention.
For abilities, I max Q>E>W, and my ult whenever it's available.
A good wave clear combo is punching a monster in a camp, and walking away slowly while charging your Q. Once it's fully charged, you dash through the wave, stunning them. Then, you turn around and E the whole camp. I also like to prioritize killing the weaker monsters first, since they're easier to kill, and you won't have a little small monster that keeps chipping away small amounts of damage.
When ganking, I like to charge my Q in the bush for half a second, before walking out. That way, once I am in a good position to engage, I'll have a full charge. Hitting your Q is important if you want your gank to be successful, as it opens allows both you and your laner to engage the enemy, potentially getting a kill.
- If the enemy burns Flash to escape your gank, I usually don't chase after them, since you just put an important summoner spell on cool down for them. However, if they're really low (100 or less health is usually good,) you have your ultimate really, and you have a decent amount of health; then by all means, go all in (as long as the enemy isn't an annoying champion like Fizz or Vladimir who can go untargetable.)
As for builds, I'd recommend building Stalker's Blade with the Warrior enchantment. Trinity Force and Deadman's plate are also good core items for her as well. Black Cleaver allows her to shred more armor with her W, so I usually get that. As for her boots, depending on the situation, you can build either Mercury's Treads, Ninja Tabi, or Berserker's Greaves.
Other good items for her include Spirit visage, Frozen Mallet, Blade of the Ruined King, Sterrak's Gage, or any standard bruiser items.
That's all I can think of for now. If you have any specific questions, feel free to ask.
If you want, I can add you and help you out in game as well (just a thought ; - ; )