A boy i like gave me his number?

Well we met in the beginning of the semester. I always thought he was really cute. We slowly started becoming friends. It was pretty obvious to most that i liked him and i think he knew too. We started having this flirty relationship and i actually thought he liked me. Whenever i thought that he would do something like ignore me and not talk to me. Well after doing this like 4 times i seriously thought i was done with him. The last day of school i let him sign my yearbook and he gave me his phone number. I don't know what to do. I gave him my phone number before but it was a while ago and i think he lost it. I even told him at lunch jokingly that i dont text guys first and he responded I dont care i dont have your number. Should i text him if so when and what should i say. I'm scared that he wont ever respond!