i have plenty experience as and against yasuo, especially as skillshot mages and i'll tell you, standing away from your minions will work. there is a huge range for you to earn xp from minions, and you should also be able to cs just fine if you take my advice.
here are a few things that will help you win vs yasuo in lane.
1: let him push toward you.
yasuo's abilities will quickly push the wave toward your tower, and if the wave is by you, it should be VERY easy for you to deny yasuo cs and get cs of your own easily. if you can, try to freeze the wave around here: http://i.imgur.com/bXysIjb.jpg (where the red circle is). if you can't freeze it there, at least try to get the wave under your turret. if you're good at csing and know how to prepare minions, it should be easy to get cs from here.
2: pop his shield with an auto attack
it's really easy for yasuo to lose a trade if he doesn't have his shield up so if you get an opportunity to pop his shield, make sure to do it. remember, he's still a melee champion so he has to go toward you for him to do damage or cs.
3: get your jungler to gank
yasuo is arguably the easiest champion in the game to gank. if he's ahead it can be risky but assuming you haven't gotten destroyed by him early on, jungler ganks are the best way to win your lane against him. he has no reliable escape besides flash and a lot of junglers are really good at shutting down his mobility.
4: once you're able to, constantly shove the wave toward his tower, then roam.
once you're level 6 and have enough damage to quickly clear the minion wave, just do that and then roam. make sure to buy a pink ward for the river to make sure that your gank isn't being seen. this is one of the most effective strategies versus yasuo.
hope i could help