A lot of good tips here and some other not so good.
1. WD40 type sprays are not lubricants as such but degreasers which will make things free up for a while and then slowly get crappy again.
2. Carby spray is a slightly weaker version of Brake Clean spray which is not to be used near paint, greased pieces, and rubber.
3. I would not put a hard garden pressure hose near my bike let alone a high pressure cleaner, all you do is push the crap inside your parts.
4. Only use grease that wont affect rubber seals, get a grease that you can use on all parts of your bike like Belray etc, not anything with lithium in it.
5. Lanogaurd is good but do not use it in hot temperatures as it will just become runny and leave your bike like an ice block at the beach.
6. Don't lube pulley wheels on rear mechs as they run better dry, lube just attracts dirt there.
Just things I have learnt over the years.