Best trick: Take a PPD/insulin syringe, draw up 1cc of lidocaine without epi- feel for a pulse and inject near it (pulling back first to check for blood). Give it a good 60 seconds to work and then feel for the pulse, hold the needle like a pencil and go. The lidocaine makes it a- more comfortable for the patient and b-allows you to manuever a little in case you 'miss'.
two finger vs one is a style thing. try them both and see which works best for you.
Best hint for any procedure: Crank the bed up so you aren't leaning over all the time. Seriously. You iwll kill your back otherwise.