how can i let my freinds play online on my 360/xbox live account without them using my profile?

do they only have to make use of mine, does any particular need to have the live membership?

Can’t, have to make an account.
Gold status is tied to a specific gamertag.. Unless your friends have their own Gold gamertags they will have to use yours..

All gamertags which want to play online need to have Gold status.. you can bring Guests online with you when you play with your Gold account but the guests will not earn any achievement points and cannot have their own friend lists..