What is the best way to get toppings to stick to the outside of loaves when baking?

I've tried submerging the top of the loaf in water for a second or two before rolling the wet side in another bowl with the toppings (seeds and flaked oats and the like) and then letting cold proof in the fridge and whilst I do get a lot of the toppings sticking to the loaf after baking, they aren't adhered particularly well and will often fall off when I'm slicing the bread. Any suggestions or tips for improvement