I know what you mean hun. Ive been cabin crew for several years now and have found my own way of memorising. I found it really daunting when i first started out.
What I try to do is spend a day on one drill, and keep writing it out until its perfect. Take time out fag, coffee etc. Then go back to it. Dont start on another until you are sure you have got it.
With the diagram, make a mental picture

of where everything goes. When there is alot of equipment such as smoke hood and portable oxygen put all over the place, I have colour coded them so at a glance I can see where they are.
When it eventually sinks in which it will continue on the next challenge
Good Luck you will be fine, its good that they have given us them now. In my other training courses there have been longer drills and shorter time to learn them.
Dont worry

All the best
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