1. I would recommend getting a cheap pair of pantyhose and cutting them into 2 pieces (left side, right side) so you could slip the shorts on over them and remove them after the shorts are on, might sound like a pain but it works for me.
2. One easy technique that I’ve used for my Tiffany is to cut the legs off an old pair of pantyhose/tights or use an old pair of stockings. Pull the stockings as high up her legs as possible, right up to her bum. You can then easily pull the tight shorts over the stocking-clad legs right up to her bum.
If your girl is wearing knickers then the shorts should pull over the knickers relatively easily.
It’s a bit more tricky if she’s just wearing a thong so you have to slowly and carefully pull the shorts up over her bum cheeks. Once the shorts are pulled up, you can then remove the stockings or pantyhose legs by pulling them down her legs.
You can use the same technique for any tight clothing.
3. I just take my time with it. I lay her off the edge of the bed to get them on her legs. Then I gently pull them up until they start to resist. Then I stand her up, leaning against something of course. Then I slip my hand inside the shorts and slowly slide them up, inch by inch, working my way up in a circle around her body, left to right, front to back. It takes some time, but like you, I like to see her legs without stockings.