*Parent spoke one language in the morning and a different language in the afternoon.

*One parent spoke one language to the child, the other spoke a different language to the child, and between them the parents spoke yet a different language (sometimes this was their mother tongue; sometimes for one it was the mother tongue but for the other parent, it was a second language).

*One week of one language followed by a week of the second language, then back to the first language, etc.

*One parent wasn’t fluent enough and just had a set time each day to go through whatever they could in the target language.

A recommended resource was Bilingual Kids http://www.bilingualkids.com/ . Other than that, you’re going to have to fit in time to relearn what you knew before–it won’t take nearly as much time as it first did, but it’ll be very important if you hope to have your child bilingual.