Manfaatkan hal-hal yang telah Anda pelajari. Jaga kedekatan dengannya. Jangan berubah menjadi orang lain.

I'm interested in that, but I only have a few mins. Can you give me at most the first 500 characters of a detailed explanation in English about that?
While being his friend, you should have learned his likes and dislikes—about girls and in general. Use these things to your advantage. Show him that the two of you have similar interests in hobbies or activities. Also, show him that you have the personality traits that he is attracted to. Don’t lose the friendship that you have created. This shows him that you appreciate him as a person. When he realizes that you are attracted to him, it will help create the image of you as “the whole package.”