[Openstreetmap] Are there any guides for creating common road layouts?

[Peter Knowles]

Hello all,

Do any guides exist for creating common road structures/layouts using
either the online or offline editors?

I'm thinking in particular of things like roundabouts, motorway onramps
etc. I know that there's no bezier curves or anything, so how do you guys
normally do roundabouts? How many points do you add in?

Regards,
Peter