Attempting to move a friendship forward into something deeper can be terrifying. Possibly the biggest risk is the potential loss of friendship with the man you care about -- and that fear is not unfounded. The awkwardness created by a professed but unrequited attraction can cause a friendship to change or diminish. You can do some things to minimize the damage, but the first thing you need to keep in mind is that a friendship that cannot withstand a declaration of romantic feelings is not much of a friendship. You may not be losing as much as you think.
Keep it casual. You know those "big gesture" videos all over YouTube? Don't do that. The environment in which you make your feelings known should be familiar to you both and relaxed.
Give him an out. It is best to meet him somewhere so you do not have to leave together if things do not go well. This will give you both an opportunity to regroup before you see each other again.
Be direct. Do not make him guess at what you are saying or make it so convoluted and wordy he becomes uncomfortable. You can either tell him straight up that you have stronger feelings than friendship for him or ask him if he has ever considered taking you out on a date.
Withhold expectations. You do not want to make him feel as though you are issuing an ultimatum. Assure him that if he does not feel the same way about you, you have no intention of changing the way you treat him. He needs to know the friendship is still safe.
Maintain a positive attitude. If you end the conversation with smiles or even laughter, the odds of the friendship remaining intact are higher than if you end with a negative tone. He is more likely to continue the relationship if you appear to be in a good mood regardless of his response.