I opted to use a spiral bound B5-sized Muji notebook here and the narrow rule is perfect for my small child-like handwriting. It also seems to take Muji gels well too (I would hope so!).
Other things I like to make notes on are major features of each of these differentials: the ones you can see below are some of the differentials for jaundice.
Like I said, no hidden tips for OSCEs aside from practice. I have formulated my own ways to tackle each station type and I'm sure each medical schools teach their own little tips and tricks too. I'm not sure I have enough tips and tricks to form a blog post though but once I do, I'll be sure to write a post about it. :)
One excellent way of gaining confidence and competence is to examine and talk to as many patients as possible on placement. Patients are interesting people and the more contact you have, the less daunting being a doctor will seem (though I am trying to convince myself with that as I'm now halfway through medschool and still sh*tting my pants at the thought of being a doctor in two years time if all exams are passed...!).