Been there.
Our DD8 started squirming when I dressed her at around 4 months. When I stopped trying to dress her, she snatched the outfit and tried to throw it as far as her stubby arms would allow. I held her up to her closet and shifted things so she could see. Eventually she grabbed something, and allowed me to dress her without resistance.
Since then, we've stopped buying her anything that she didn't pick out herself, because if she doesn't like it, she won't wear it. We guide her fashion choices based on the weather, the occasion, propriety, and expense, but otherwise give her full control. It's not a battle worth fighting. And by letting her have control over things like this, it helps her become a confident little girl.
Our DD was right about your DD's age when getting things on the clothes became a major issue. She'd spill a little water on herself and DEMAND to be changed. We refused to take the bait on this, and dismissed her with a casual, "It's just water, it'll dry off." And then we let her stay wet and upset until, sure enough, the water dried off. She found that pretty fascinating. We knew the message had sunk in when she later suggested the same thing would happen with a spaghetti stain.
We didn't have the issue with diaper wetting, although it may be because DD was potty trained before 2. It was about that age that we were busy convincing DD that we knew what we were talking about (we were a little too successful on that, which led to an interesting exchange when she was 4), so in this situation, I'd probably tell her she's not wet... and then when she insists I'm wrong, I'd undress her, hand her the clothes, and say, "Show me the wet spots." Repeat this drill several times, and she should come to trust your word on this.
