This guide works well in conjunction with the two other snake-related Instructables:
Snake (or Hook) Stick - which can be viewed here.
Snake Tube - which can be viewed here.
There are a few things to remember when dealing with snakes:
1) Snakes are not toys. Only catch a snake for qualified research purposes, or if you absolutely have to. Remember, it's stressful for the animal to be captured.
2) Start small. Don't try catching a 2-metre cobra on your first day out, you'll come off second best. Start with practising the wrist movements and techniques on a rubber snake or a thick piece of rope. The rope works well because if it's as thick as a snake, it reacts a little bit like one in terms of flexibility. Once you're confident in that, move onto a harmless species, and practise on it. Preferably use a specimen bred in captivity as opposed to a wild snake. Captive-breds are more used to human interaction and you'll therefore cause it less stress.
3) SNAKES ARE NOT TOYS.
4) Know your species. Pretty basic, but important. Know what snakes you're likely to encounter around your area, some are more aggressive than others etc etc etc.
5) SNAKES ARE NOT TOYS.
6) Focus on the snake. Don't answer your phone with a snake in the hand, again, you'll come off second best.
And this is probably the most important thing to remember when dealing with venomous snakes:
COMPLACENCY KILLS. Just because you've caught a hundred snakes successfully doesn't change anything.
Finally, this is obviously just a guide - I recommend attending a handling course or something similar where a professional can teach you face to face about dealing with snakes.