Help on litter training

I've been fostering my first foster kitten and I've had him since he was found in someone's yard at just 2 weeks old and it's time for litter training... Any tips other than putting it in his room at night and reminding him where the others are during the day? I've always had "mama" to help but this guy was an orphan... He's went potty once but not since (in the litter box on his own) so if anyone else has advice, I'm all ears

Sorry I missed this post. How is the little one doing? The only advice I have is be patient.

My cat, Bella, had kittens awhile back, and it was pretty hard to litter train her and the kittens. I don't know if you have tried this, but what I did was take the kitten into the place where the litter box was, and then kind of "paw/dig" at the litter while he was watching. The litter box was new and clean, so no worries lol. Then I set him in the box, and while he was in there, I "pawed" at it again. He might not get it the first few times, it took awhile for my kittens to figure it out. Also, when you find a mess he made outside the box, pick him and the mess up, and put the mess in the box. Make sure he sees you doing that, and maybe show him that it's in there. And when he finally goes in the box, make sure you reward him in some way. 

Thanks for your replies... Just a couple of days after posting this, he started using the box like a pro!! Hehe