Oh where to start :-)
I hope you love it as much as I did my first time, think I'd had a bike about a year before I did Brands and I was immediately hooked !
I'm sure it depends on who you ask as to what you do, if you're determined to "be the best that you can be" you will start running / cycling in order to shave a second or two off your lap times like Wes does, or if you are more like me you could just getter a bigger bike and train at McDonalds ;-)
It would be worth reading the threads for our Club trackday at castle Combe as a number of new riders were asking the same questions: http://www.wiltshirebikers.co.uk/sho...h-Castle-Combe

It 's worth a look at www.trackdayriders.co.uk too, a great site if you don't look at the "What have you broken - pics" thread lol
You could also do a smaller track before the big day at Silverstone (a HUGE track) to give you a bit of confidence.
Keep an eye out for our Castle Combe day or anything at Llandow.

Re how not to destroy your bike, I would suggest not crashing. I've tried crashing and not crashing, and not crashing is definitely better :-)
Feel free to PM me if you have specific questions, I 'm not at all an expert but am happy to try to help.
Cheers