Yeah, I would say repetition and praise too. Steph can recognise the letter "S" as 'her' letter (lol, its so funny), but that's through a lot of reading and talking about alphabet books (like we talk about names of people we know and words of each letter as we go through the book. Sorry, just realised I haven't said much helpful, just listen to Lime Slice.

Oh, just remembered, I think you can get books where they draw over dotted lines to write letters. Hope that helps, good luck.