The biggest mistake you can make it to think that everything has to be perfect.

Building your first plane, be it ARF or kit, is plenty stressful ... it is an airplane right ?? ... and airplanes need to be perfect or they will fly like corkscrews, right ???
See line one above and chill out, its not going to be perfect and its not going to matter.
I know you don't believe it won't matter; but after a few more builds you will believe it.

Even though gluing the big pieces together is what you are scared of that is the easy part, all of that will have pictures and instructions (assuming that you get a top tier ARF, if you go bargain shopping at auction or the other direct from China importers then there may not be much in the form of instructions for anything).

Getting the pushrods installed so that the servos use 100% of the travel to achieve the desired control deflection is important, spending the extra time to understand mechanical advantage and to get this right is worth it.

Don't be in a hurry, you can do it once correctly and it will look nice, or you can tear it out two or three times and have it look like it has crashed and burned, its your choice.

Don't even mess around with 5-minute epoxy, 30-minute epoxy just works better and its pot life is plenty short anyway.
The 90% Isopropyl alcohol that you can get at Wal-Mart works fine for thinning and cleaning epoxy.
There are those that will carp on and on about it, but 90% alcohol works fine.
The only time you should be thinning epoxy anyway is to use it as a fuel proof coating, the rest of the time it needs to be used at full strength.

If you get stuck or need help ask for it, experienced in-person help is the best kind, pictures usually help here when asking a question.