Hydrangea question.

I have a dwarf variety of Hydrangea called "little livin' Rosie". It remains small and compact and the flowers start off white, go through a creamy stage and then start going through various stages of pink before turning a deep pink at the end of the season.

As you can see from the picture below it is a lovely variety but I'm not sure what to do with the flowers when they start to die back, which they'll do over the coming weeks, there's still a fair bit of life left in them yet. Do I just deadhead them all or leave them to their own devices?

 

Leave them on till next spring. Some will disintegrate and blow away during winter weather, but if there are any left in late Feb or early March, trim them off then, taking the stem back to the next set of healthy buds.

Yours looks a super little plant!

 

Yes - the paniculatas get pruned in late winter/early spring @Esoxlucius , depending on the conditions at the time.
Some people cut back hard to get bigger flowers, and some cut back less, to leave a larger framework, which means smaller flowers, but more of them. The branches of bigger varieties can be very heavy if cut back hard, and flowers can droop badly and need a lot of extra support, so the latter is a good way of doing it, but it also depends on the site and the weather as to how big they get.

A smaller variety like that one should be fine with the method described by @ViewAhead . It certainly looks happy