Steady on space cat, he is just training at the moment
Can't you remeber what it was like.
A1pacino, when ever I used to come across things like this i got my pencil out, drew what I had and then re-drew it as I needed it.
This allowed me to carryout the thought processes in my head and visually.
We all have different levels of Kinesthetic, visual and auditory learning (KVA they call it)
By using all these 3 types you will access and formulate the solution for yourself.
Space cat is right to a certain extent, but then again rote learning makes things stick and allows you to react much quicker.
What ever you do don't panic if you come a blank. Take a pause, reach for your pencil and paper and draw it, even in the exam, I and some of my student friends did, there was no problem from the invigilators.
2 of us had degrees in technical subjects, but we still needed to visualise the problem.
Better safe than sorry and going at it like a blind bull in a serving crate
BOL