It's best to get hold of him by the base of the tail and then lift him onto you hand (maybe the back of your hand if you think he may bite!). I wouldnt chase him around to try to get him, it may take a few tries to get hold of him, I find once they feel securly held the are calm. You could try getting him to go into to tube and then pick it up and get him into your hand. Mice can literally fly quite a distance so I would advise keeping your hand in or above his tank so if he gets away from you, you wont have to chase him around the house for days!