There are a few airlines where one must flip over the seat instead of just reclining as far as possible to make a flat bed. Some SQ aircraft are an example of the flip it over technology. IME on SQ in FC, if get up after dinner, for example to use the lavatory or even just to stretch, a FA will appear and ask if I'd like to have the bed made up now.

I also often follow the trick of using the duvet/quilt/blanket as a mattress pad. If the cabin is empty, you can often get an extra duvet/quilt/blanket for this purpose.