If you spend a lot of time with the guy you like, you should then ensure that he will miss you. The effective way to do this is to create a temporary distance between you two just to let him realize how important you are to him. If you do certain things together you can skip some of them to let him know that those things are different without you. This will make him think more about how important you are to him and the ultimate results will be the two of you ending up together.