I found it quite difficult, but I am still learning.... getting the right sizes was straight forward enough, but doing the lining was hard, and despite me thinking it would be simple... dying it all was quite a challenge as well.
One thing that was a massive learning experience was the carving... I put far too much water onto the leather, spent too little time on some areas and far too much on others... its not as easy as it looks when you watch others do it.
Stitching, I love stitching... so that to me was the most enjoyable bit. One of my hobbies is making chainmail, so the process of saddle stitching is like a dream. I did find it hard to get a consistent stitch at first, but once I got into the swing of it, I'm quite pleased at how it turned out.
Best bet Arya is to grab some leather and have a lash at it. Its a lot of fun and very rewarding to do... bit frustration with the dying when its not going right, but other than that... thoroughly enjoyable experience.