Work Capability Assessment interview tips

What is the best way to portray ourselves at a Work Capability Assessment interview? The assessor or 'nurse' has all the information from the attendee and all the relevant medical evidence; so it seems to be the purpose is to try to trip you up and make out the points in the application aren't really descriptive of our conditions. I'd like some tips for us all on the best way to come across at the interview so we don't look like we are actually capable of full time work, when we are not.

I did my daughter's WCA as her appointee. Not sure whether I had somebody with insight but it was largely painless. After checking diagnoses and medication she wanted an account of a typical day so from getting up to presumably going to bed although we didn't get that far as she said she had enough information. It tookabout thirty minutes and I got the results in just over a week including a bank holiday. Every day is groundhog day here so I found it easy to describe a typical day but it might help to have a few pointers noted down.

Best get it recorded I guess!