As many here complain, I just wrote a comprehensive post, tried to Edit it. Gone, moan over! Why is this site so useless? only due to the posters, both good and moony.
Edinburgh is not just the Festival and Fringe, there is the Tattoo! Busses come from all over Europe for this event. Best seats are on the East stand with the castle as a backdrop, and sometimes a super sunset to boot.
At the end of each performance there are fireworks, and good too. The folks who live cheek by jowl with the Castle are fed up with all the noise and either use earplugs to rent heir houses out.
They have a rehearsal evening about a week before , tickets available. Worth looking up as they can easily sell out.
Re accommodation Uni halls are good as well as hostels, some are very near to the action. Motherwell is a fair journey away.
For a bit of peace from the throngs of tourists there are th Botanical gardens where they also holds shows 23/27 bus from the Mound.
I confess not being around town then, as its too busy and pushy, tho any local will help you.
Enjoy