stay's open, gotta push really hard. Might need to loosen the cap off the break fluid reservoir and wrap a cloth round to catch any overspill. Once its all done you might need to syringe(sp?) some of the fluid out to get it down to at least the max. level
Don't think you really need a practise, just take your time to do the first and remember or make note of what way things come off. Took me about an hour to do the first one and 20mins to do the other first time i did it. But a practise aint aint gunna hurt anyone so if it reasures you then go for it.