I run the card Impulsive Maneuvers in my Norin the Wary commander deck and I've come across instances where the creature that I have to flip a coin has Double Strike, how would it work for each instance for when I win the flip, or loose the flip?
So your creature with double strike attacks and you flip a coin for Impulsive Manuevers.
During the first combat damage step, the damage dealt by your attacking creature will be affected by Impulsive Maneuvers’ effect, so it will be doubled if you won the flip or prevented if you lost the flip.
During the second combat damage step, your attacking creature deals damage normally since Impulsive Maneuvers’ effect only applies to the first time the creature would deal combat damage after the triggered ability resolves.