Be a tutor, not a punisher and don't strive for early perfection...
The earlier you start teaching a second language to your children, the better.
Kids must be exposed to consistent quality vocabulary use in both languages in order to learn two idioms. People frequently believe that children's brains are like sponges and that they will simply pick up a language. They actually come from language-rich environments where both parents have college degrees, provide homework assistance just as soon as needed and frequently take their kids to the library.
Learned skills in one language can be transferred to the other. Despite the fact that each idiom has its own set of rules, there is something akin to a central bank of language knowledge. This emphasizes the importance of strong first-language skills, as they will be used during the child learns the second idiom.
Golden rule: One Parent, One Language. One parent always speaks one language to the children. This is not the only way to teach an idiom, but it promotes increased language input and success in learning.
A bilingual child can be raised by monolingual parents. The brain that is wired to learn is the same one that is wired to die. Learn alongside your children, and be aware that you will most likely become more reliant on outside assistance, especially when your child's skills surpass yours.
Electronic media, books and foreign babysitters are all excellent ways to supplement the exposure to a second language.
Learning a second language can also help you avoid getting Alzheimer's. According to a recent research, bilingual people's brains function better and for longer after they develop Alzheimer's disease. Compared to monolinguals, the disease takes four years longer to develop.
Be a tutor, not a punisher. Do not strive for perfection. Just keep in mind that whatever you teach to your children as a second language will be a gift for the rest of their lives.