I don't think it is necessary to use all the technology that your children are using to help them understand how to use it safely. There are way too many apps and other things that they can use and will use in the future for you to be able to use all of them and then teach them proper usage. I feel that if you explain basic concepts like don't give out information on where you live, don't meet up with someone you only know from online, don't spend more than an hour a day catching up with friends, etc. and why these guidelines are important, those same ideas will work in twitter, snapchat, instagram, and such without you needing to be on each one. I do suggest you learn one or 2 of these "social media" technology to see what happens and what might happen.
Once they know why certain behaviors are important they will better be able to decide on their own what they should and shouldn't do in most situations.