Change gear to move the chain out of the way - so the chain is on the smallest cog.
Undo the brake quick release - push the brake arms together and remove the brake cable from the cradle.
Lift bike over to sit it onto its saddle and handlebars.
Release wheel quick release lever.
With your left hand place your thumb and fingers on the Derailleur mechanism to open the chain up - so there is a wide space to pull the wheel out.
Pull wheel out and then release the Derailleur.
To replace the wheel follow the same procedure in reverse.