don't just jump in with 8.1 preview because then you have no reference point to a fully working tested and developed o/s against a developer preview that hasn't been released for a specific device and apps haven't been fine tuned to run on it properly , it works well , but it caused big battery drain on my 1020 and for a new user to just install the dev preview might give the new user the impression that the 1020 isn't as good and smooth as it should be ;-) please note I installed a clean install and didn't restore a back up 8.1 is fresh and funky and has some great features but its also a dev preview meant for devs to get their apps ready for 8.1 and to test them on devices ;-) by all means install it you can downgrade but I just think installing it straight away is a bit of a bad idea ;-)
as for tips
defo set up your home screen right , it might take time , but a fully working personalised home screen will help you get the most out of windows o/s
turn auto back up on as with inbuilt storage if there is an error your pics are gone forever , onedrive works great and the pc version sits there like another drive for easy copy and paste between pc and onedrive ;-)
get a screen protector , gorilla glass is scratch proof not resistant ;-)
make sure you have black installed and not amber as black takes raw images in dng format and the jpeg processing is much better ;-)
have a good read of the forums loads of info over the pages ;-)
apps
audicloud - great soundcloud client
tuneinradio - great for internet radio
metrotube - great youtube client
nokia camera - best camera app make sure its updated
pro shot camera - another great camera app worth checking out
6tag - great instagram app
endomondo - great sports tracking app
gmaps - great google maps app that can work with nokia maps to get voice directions
tile live score - great for following a certain sports team
nokia mix radio - great music app and music player well worth using
flashlight-x - flashlight app though be careful as when camera is activated ois is activated so prolonged useage wont be great for the device
have a look through the store , many great apps like movie apps , music apps that let you download items and playback through the device ;-) also don't forget to check the collections section of the store , there is a red stripe discount section and a nokia section which are both worth checking out as are the other collections ;-)