Welcome

As for taking notes: I've just started using the online service "evernote" (evernote.com). It's free, it's simple and it works.

Apart from that, I juggle down some things in my paper notebook and other things on my phone (plain old "dumb" phone with a note application - I can display any of those notes on the screen for easy reference if I want to).

What I use depends on the application. For long time reference (information you might need at some distant future), nothing beats an online, searchable service. All memorable survival tips, tricks and hints would go there. For things such as shopping lists or juggling down an adress I use my plain old paper notebook. For things I really should remenber (pick up X at location Y) I use my phone and display that on my screen.

Life became easier when I systematically stopped using my brain as a combined storage facility, calendar and task manager (i use todist.com for that!). My brain works best when I don't add the stress of all those details I really MUST remember. Writing it down (on the web, on my phone or on paper) is a great relief - I can consentrate on productive things instead of going "Oh, I SHOULD have remembered that" or "I MUST NOT forget this" every 10th minutes. It really breaks consentration, workflow and adds stress.

Your brain is for thinking, not a mediocre task manager/file cabinet.