We all do nerve blocks. Some more than others. Here are some hints. It is more ED based but a block is a block is a block.
http://www.emdocs.net/pain-profiles-nerve-block-tips-tricks-sterility-safety-simulation/

Pain Profiles – Nerve Block Tips & Tricks: Sterility, Safety, Simulation – emDOCs.net – Emergency Medicine Education

How can you maximize the success and safety of nerve blocks? This post from David Cisewski in the Pain Profiles series provides you with tips and tricks.