Ah yes, I know what you mean. It was difficult to get DD in the Ergo when she was younger/smaller. But then I found it got easier when she was slightly older/larger. She would "help" me get her in it. I held her in front and made a "game" of it by swinging her back and forth, "1, 2, 3!" and I'd swing her onto my back on "3". I would have to bend forward so she can lean on my back without falling while I get one of the straps on my shoulder. Of course I would have one hand reaching back to hold her in place on my back so she doesn't fall off. Then I'd use my hand to pull the back fabric up around her bottom/back before I tried to get the 2nd strap on my shoulder. I little bounce & adjust, then snap the connection on the front and we're good to go! It's pretty much like the instructions they give you.
At first I had trouble with the dismount. This was back when DD wasn't even standing yet. So I'd always have to make sure we got back home so I could use the bed (or even the sofa sometimes), leaning back so she'd lie on the bed before I unbuckle everything. ... then it got way easier once she was standing. I would bend over slightly, undo the front buckle, take of one shoulder strap, and grab hold of her while swinging her forward (it's almost the reverse action of getting her into the Ergo), and then place her gently on the floor where she can stand on her own. Sometimes I make it fun for her by swinging her a bit back and forth before I put her down, she loves that.
If you asked me early on, I would have said the Ergo was awful. But after DD was a little older/larger, it was GREAT!!! She loves riding in it. And I can't imagine doing without it.
Hope this helps...