I have hardly ever looked at beta before either but I might start to do so now saving some long winded measurements and calculations.
all of this leads on to the STOP/LOSS....
to be consistant with the same amount risked on each trade - the percentage of share price to the stop/loss level would also have to vary..... ie a greater percentage for a high beta stock which has a lesser amount wagered per increment in the trade,,, and a lesser percentage of the share price for a stock with lower beta but a much larger amount in the trade.
so that answers the question of "HOW DO I DETERMINE MY STOP LOSS PERCENTAGE" in logical way.
all my own opinions of course which others are welcome to comment on or disagree with.