Guys are easy prey when it comes to turning them on by text to be honest; they are not as suspicious as us so will believe more of what we tell them ;-)
Be careful though, if this is a guy that you are not actually planning to meet and have a relationship with, don't tell him 'all the things you will do to him' in case he tries something with you that you are not ready for.
You could tell him that you had a dream about him last night and you were wearing...... (you can fill in those blanks!) and he seemed to like it because.....(you get the picture).
The best advice is to take it slowly, build it up gradually, flirt with him, play with him, keep a little back. He will be eating out of your hand in no time ;-)
Another word of advice though, never send photos! As much as he will beg, don't do it. These photos have a nasty habit of turning up on the internet or being shown to all his mates. You are better than that.