Putting your hand out for smelling is great for dogs and cats but not snakes! Snakes are adapted for picking up scents so he smells you already. Besides, it is a threatening action to them. Even if it doesn't result in a bite it would be stressful. Generally avoid movement around his head. You can go right in and pick him up at the widest part of his body by lifting underneath him and then adding a second hand for support. However, I've found that opening the cage and giving them 30 seconds or so before I touch them seems to prepare them for handling. Some people will stroke that wide part lightly so they know they are about to be handled. I rarely do this with my BP though because he is so docile.