Suggestions For A First Time Mom On How To Put Baby To Sleep?

My sweet niece just recently became a first time mother and her baby boy is keeping her up at night. She recently asked some advice on how to get him to fall asleep on the nights he wants to play? lol My suggestion was something that saved me with all three of my children....

that magical purple bottle and no, I'm not talking about Benadryl or any type of cough medicine! It is Johnson's baby wash with lavender which apparently helps baby relax and soothes them to sleep. That was a miracle wash for me and they have the lotion to go with. What suggestions do you have for putting a small baby to sleep?