I personally LOVE D2, its one of my fav steels and I have many knives with D2 blades.
Just like you should do with any knife, wipe it down after usage, especially cutting anything that leaves liquid residue on the blade.
I have never had any issues with rust on any of my knives, D2 blades included.
If your worried about rust make sure to use a light coating of oil to keep it lubed.
Personally I'd recommend "Aegis Solutions EDC", its liquid form, just spray it on wipe it into the blade and wipe the excess off.
One coating lasts a minimum of 3-4 weeks and can withstand heavy sweat without any issues or rust forming.
Take a look at their website and YouTube channel to get some more info.
Just my .02