The old days of the nitrous button you hold are almost gone IMO. Now a days the safest way is to have your setup is to have one switch that activates your system (master) then after your system is active there is a switch mounted on the TB. When you go Wide Open Throttle the nitrous is then spraying. So it's spraying the whole time you'll be running. Then when your one you turn off the "master" switch.

My main recommendations are a high volume fuel pump, Adjustable cam gear (makes life easier), and colder plugs.

After that just spray and be safe.

Take it easy.