You have 2 possible choices. Solo top or duo bot, ill cover both here.
Solo top you won't be harassing with Q until lvl 4ish or at least until you have your
for the mana regen. If you must harass, then do it in retaliation or little Q jabs only(but keep enough mana for your E incase you're ganked) and auto attacks. Your main job here is to farm until you have your philo and sheen. You'll need help from your jungler to successfully gain an advantage, or if luck plays a small part and you pull off a kill on your own. Its hard, but not impossible to do.
Barrier has made it much easier to duel with others.
Duo laning is a bit easier, especially if you have a support sustaining you or if you are the support.
is by far the best champion to duo with in my opinion, she has everything you need but any ranged champion is fine. For all of the early game you'll be farming to get your sheen as fast as possible. Also, poppy is a beast of a counter-jungler. Buy an early ward, time when blue is taken and place it at their blue bush. More often than not you'll be able to kill their jungler single-handedly or at least steal blue.
You'll want a partner who has a stun and/or can harass. This'll give you both a chance to burst an enemy down. A stun will allow you to line up your charge.
Excellent laning partners:
Good laning partners:
Mediocre laning partners:
How to last hit under the tower
Melee minions: Let the tower hit them twice, then attack and kill.
Caster minions: Attack once, then the tower attacks, then you attack and kill.
Master this and you will hardly notice a difference in your CS. You'll at least be equal to your opponant. Although you just have to accept the fact you'll have a tough time against