My 16 month old just laughs when we tell her 'no'. Does anybody else's do this too? I feel like I need to change my language because she understands quite a lot, but I don't want it to get complicated. Any positive reinforcement strategies you've used, or anything you can think of to help her understand?
My little boy used to do this too. Using positive language is a great idea. You could try and tell her what she can do, rather than what she can't do.
For example, rather than 'Don't draw on that', try 'Pencils are for drawing on paper. Would you like to draw on coloured paper or white paper?' (and offer some paper for her to choose from you). Rather than 'Don't cut that', try 'Scissors are used for cutting paper or playdough, which one would you like to cut?' (and again offer simple choices for her to pick from).
At this age, children are developing their independence and like to feel they are in control. So provide opportunities for them to feel in control. For example, if you're struggling to get her dressed, try 'Would you like to wear the pink t-shirt or the blue t-shirt today?'
Toddlers are little monsters, aren't they! Mine was doing this too but I take her away from what she's doing, say 'No' and shake my head at her. I also explain why I've done it. If she does it again, I say 'No' firmer and try to distract her with something else. It's so difficult trying to work out how much they can understand.