Well, your fights before lvl 6 or a 1v1 fight, always start with W, but do not use it to get closer, use smite instead, or just wait. After use W you press instantly Q to stun, hit faster and break armor, its really important. in the end of your W just cast the second time, but you can cast before, remember, when the enemy has a lower life, more damage it will take from it, but at early game you will cast as late as possible (at late it is just cast Q, hit twice and W again, really.) DO NOT USE YOUR E TO SIMPLY GIVE DAMAGE, your E is important to stop the fight or to deny damage, so analyse the champion that you are fighting with and wait for it (like a kayn, for exemple), BUT, when you do cast E, always aim to a wall, its important, either the damage either the stun,you can cast to do it too, but in a very specific situation that you won't need it to deny damage or it is very convenient. you can always cast E after Q to try to push to a wall too.
With R open, just try to use it in close range, hidden, after that, 1v5 or not just try to kill the guy as fast as you can, then just run alway or continue the fight. its basically the same thing, starts with W, then Q, some hits and W again. It will give a really nice damage with Draktharr and collector, so sometimes when the enemy is half life will be enough to cast again.

It's not 100% optimized, but what I do is: Get help from bot with the buff, then go for E and cast it in the biggest camp (like gromp or the giga stones) then smite it and W, you will kill it very fast. After that go for the third camp, E and W to start again (you need to make the camp have a lower life to use W, its better) and full clear the next camp, using smite in the very same thing again. you will be at somewhere bettwen 3:30 and 3:40. Next you can gank one time, or twice, but be fast, reset and restart cleaning the camps, you HAVE TO be xp ahead from the enemy jungle ALWAYS. She can do drag at lvl 4 with only 1 smite, but it will take some time, so do it carefully with bot pressure and jg at the other side or either lvl 5, but you can force it, you will end it almost full life (just carefull, when someone appears, you will attack it, no matter what,so dont force it when you know that someone is coming, you will look like an bot)