Teaching your kids to be bilingual

So. How are you all teaching your kids to be bilingual. What age should I start teaching them. How do I teach them. It took me 7 years of being with my husband to learn Spanish. Him and his family taught me along with watching telenovelas and reading everything in Spanish. I just dnt know where to start to start and even tho I am fluent I can't speak it fast and I still student a little bit. Any advice on how to get better and be able to prepare to teach my little ones when they get here?