First ask your self that what made you like him, what make him different from others, what did he do to make you fall in love with him.... You'll have some answers for the same... And let your best friend know that why you love him, what makes him special to you.. What's his importance in your life and what your life would have been if he was not there with you and what difference he has made by being there with you.. And at last tell him that you find him the best man to spend your life with and that you love him truly from the bottom of your heart.
Take Care.....
Take Care.....