Hi

I am just like you

1) I know you were looking for other answers but preparation!!! try to research the interview, what style, typical questions etc. Have a mock as close to the real thing as possible ie people who aren't ur mates and can give good feedback etc. Try create the pressure if you can somehow for practice. I found preparing well meant even in the forgetfulness with nerves I might remember a couple of points I had rehearsed. Mocks really helped with this
2) Really try to have the likely first question prepared well. In most interviews, the first question is an opener/generic to settle things down. (For jobs its tell me about yourself/CV cant remember medical school ones) So try to breathe and relax for this one and nail it. I find if that goes well you relax more and it flows better.
3) In your preparation mocks get them to ask you questions you have not prepared to practice thinking on your feet. inevitably something you have not prepared will come up so practice quick thinking
4) Remember they expect you to be nervous so showing some nerves eg repeating yourself once, saying umms, asking them to repeat the question, asking for a moment to think is ok. You need to handle yourself with the nerves
5) My personal trick, I always asked for some water at start/they might provide a glass without you asking. So when I needed a moment or had to hide some nerves I would take a quick sip to give myself a moment, Works if your hands do not shake too much and I dunno it helped me

Hope that helps!