Well, it starts with the flux capacitor. Once you maintain a power source that can generate 1.21 gigawatts of energy, you'll have to maintain 88 miles an hour and you'll find yourself opening up a path to travel through time.
Once that's done, you've got to make sure coefficient bonds maintain their integrity. For that, you have to go three levels deep - remember the rule, go one level deep to extract an idea, three levels deep to put an idea in.
So, you got your path through time and your idea - what now? Well, you'll need a Maester with some Milk of the Poppy along with some dragonglass (some say that you can use some Valeryan steel, but I don't personally buy that - but if you have some Valeryan steel, don't be afraid to use it). If you know someone who can get you to Braavos, then you're even better. There might be a back door through the quantum realm, but you'll need to whip up some Pym Particles - and who has time for that?
Good luck, been a while since I've done PChem. Double check your math in case I didn't carry the one.