Definitely change on the floor if you aren't already. 1 year olds are super squirmy. I usually chase after mine while i'm changing her. For poop it's tricky because I don't want her to run away so I try to distract her with something she doesn't normally get to play with (like the pack of wipes). When they are slightly older like 18 months I've resorted to handing over my phone as a distraction for a few minutes.
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