I present pictures for how I wrap my seedlings for those that like that sort of thing. I am of the opinion that if your at least 5 years of age... you should be as good with these simple techniques.
Important: Do not crush seedlings. Place stretched out parafilm like a drape over seedling that is off center as in picture 1. Lightly pull down without exerting force on seedling. You can reposition one hand or get a helper to lightly hold seedling in place if you need to, but seedling should not move if no pressure is applied. As your wrap a bit at a time around the stock... your seedling will naturally be drawn into the stock. If at the end you suspect not enough pressure is on your seedling or your seedling is not secure enough... you may then make a light scrunching motion at the scion where you first wrapped the scion. This should draw your seedling down a bit more and create a very tight union, but be careful... it is easy to get that seedling union too tight. This will result in a smashed union and your grafted seedling will eventually turn to mush and or dry out.