Si crees que no te vas a acordar de todo lo que tienes que comprar, haz una lista.If you think you're not going to remember everything you have to buy, make a list.
Tengo que tomar muchas pastillas al día, y siempre me olvido de alguna. - Haz una lista.I've got to take many pills everyday, and I always forget one or the other. - Draw up a list.