Article: Although it can be nerve-wracking, spending one-on-one time together is a great way to strengthen friendships. Decide on an activity that you will both enjoy and invite him to join. When you invite him, try to find a balance between being open and specific. For example, if you know he enjoys bowling, ask him if he would like to go bowling soon. Not providing an exact date allows for flexibility, while specifying the activity shows you have taken note of his interests and takes the pressure of planning off of him. Your brain associates positive experiences with good feelings, so try to keep your conversations and shared activities upbeat and fun. Soon, he'll associate spending time with you with enjoyment and will want to spend more time with you. Do your best not to make promises you can't keep. When making plans, try to choose a date and time that you know you can keep. Keep in touch and be communicate with him consistently. Failing to do so may make you seem "flaky" which, in turn, may make him feel that you don't care about him.

What is a summary?
Invite him to do something with you. Keep your interactions with him positive. Be reliable.