Not as specific as loading mono on fixed spool but a few tips to make things a little better.
I would always straighten line out first and give it bit of a stretch if you try and reel it as packaged you could end up with bit of a birds nest and as flylines are only 30-40yds long can easily be laid out on lounge floor or laid down stairs. Be careful if WF line as there will be a tab to specify the reel end to be attached to backing.
As for the backing I would usually use a cheap braided mono nothing too fancy needed as its only really there to fill the spool and stop tight coils in the line although have had times on Rutland when a decent fish has taken off and stripped backing from reel decent Knot needed either nail knot backing to line or as I now do feed line inside braid and glue and whip. Can be a bit tricky judging how much backing to use as ideally need enough to completely fill spool with flyline attached. Some will wind line on spool leader end first attach backing and fill spool but this will then need to be stripped and replaced backing first any knot will suffice to join to spool as doubt you will ever run out of backing on reel.

As for the leader end I make my own braided loops from the backing used and attach again by sliding around an inch of flyline into braid small dab of glue and whip to create a small joint. If you try this dont have the loop too long and try to butt line right up to base of loop will stop any hinging between line and loop. BTW been using this method for about the last 20yrs and never had one pull off yet, now thats tempted fate!

All sounds a bit long winded but hope this helps