"I know you're supposed to try new things in bed, but we don't know where to start!"
I know you're supposed to try new things in bed, but what?
I've tried new positions but other than that I don't really know where to start. Neither of us are into role play.
Grab a few good general sex books for inspiration and flick through them for ideas. Mark things you like the look of with sticky notes in one colour, your partner does the same with another.
The pages both of you have marked you try first. The rest are negotiable once you've broken out of your comfort zones.
You could also take turns to plan a 'sex night'. The person whose turn it is decides what you're doing (choosing from what you've marked in the books), when, where, how, organises any props you need, and is the instigator.
This forces each of you to adopt different roles as giver and taker.