how to quit my job?

i really can't stand my job. i know they are going to let me go. i have a weeks vacation that hasn't been used yet. should i wait till they fire me or just quit? i've been there for 6 months. i know it'll look bad on my resume. use my vacations days now and go to interviews or use the vacation days, go back to work and wait till they fire me? if i use the vacations days for employment search, should i give them a two weeks notice before or after i start my vacation week?