1) As mentioned above, Apple's website helps.
2) Schedule an appointment at an Applestore. They teach you how to use Macs. I've never done this (I like to figure things out on my own), but if the transition is difficult for you, such a meeting might help.
3) You'll learn from above, but get used to the trackpad features. Three/four finger swipe up, three finger swipe left/right, etc, setting up different desktop windows and utilizing them (it's almost like having multiple screens). Very good for productivity, the main reason I like Macbooks so much.
4) Set up iCloud properly. If you have an iPhone, the cloud app is really useful. I have my iCloud set up to not sync photos, but to sync most other things (notes, calendar, etc). The biggest thing is that anything I put on my desktop is set to sync with iCloud, so I can access files I have on my desktop from my phone. Note that you aren't interacting with your computer, but with the files that are stored on iCloud.
5) Any other advice really just depends on your needs. You'd have to give more of a description of what you are using your Mac for.