Most of us struggle over naming one child at a time, nevermind two - three or perish the thought, even more. So if you are faced with having multiple names to come up with what should you take into account?
A lot of people tend to opt for names that start with the same letter, but of course sound different. This often seems to be a good mix of allowing them to be different but having some sort of link between them.
Look at literature
Are there famous people or partners in crime as it were in history that you want to take the names of? Maybe not laurel and hardy, but you get the idea.
Myths and legend
These are ripe with pairs of twins or groups of objects - why not go for some of these? Or even planets, moons, Greek legends for instance - take a couple of names you like there from. If you can be called Venus, then why not Mars too for isntance?
Ignore the twins factor
Of course, the simplest of all is just to ignore the fact they are twins and just pick two names that you really like! The key is to try to be consistent, so if you pick a wild name for one child and the others is more conservative, this could be a recipe for disaster further down the line.