Looking for the absolute best way to be a Salesforce Admin. 

I've only been working with Salesforce (mostly uploading info ) at my new job for about a month. I won't be doing much with it but want to become an Admin... I did some research on the topic and feel that I would enjoy a career as an Admin but I need help as we do not have a seasoned Admin. My supervisor has just learned the basics somehow but he is located in Berlin so I can't really learn under him.
Please help.

1)Will trailhead be the best way to study for the exam? is so:
    A) how do I know I am on the right trail on trailhead??

2)Do you recommend paying for classes? if so which ones?
3) any other tips would be helpful.
4) Is there another rout of Salesforce that is better that you enjoy?
Thank you guys!