I agree 100% with the "think about the kind of jobs you think you will enjoy, learn what degrees and qualifications they generally require, and try to structure your education and extracurriculars and early jobs towards that". And when you think about jobs you'll like, think about the pay, ease of getting the jobs, and future career prospects. You're off to a good start if you like science/engineering, be careful with "humanities" degrees.
My example - I really liked history, and math/computer science. Now it's POSSIBLE I could have gotten a dream job as a historic researcher or archivist with a museum or something, but most grads with just bachelor's degrees in history end up teaching. Now you might love teaching, that's great, but I didn't think I would (I had just seen how bastardly we students could be to our teachers - I couldn't imagine putting up with that for 30 years
) So I went the computer science route, I was good at it, I LOVED it, I loved solving problems and making stuff work, it paid pretty well then REALLY well. And I read a lot of history on the side
See if you can take some aptitude tests, in HS we took this thing called the Kuder career aptitude test, bunch of multiple choice questions and it spit out the careers it thought you'd like and do well at - and I felt it was pretty spot on for me. History, Math, Computer Science, Accounting - and I downgraded Accounting 'cause I thought it'd be a bit too boring, and Math had the same problem as history, with just a BA it's really hard to find a non-teaching job. And I really didn't want to spend years after a bachelor's going for a higher degree, I was kind of burning out on school even then (and not exactly flush with cash).
Anway, I'd call local Community Colleges, ask for the guidance department, and see if they offer those kinds of tests, ask them what the requirements are - even if you have to take 1 course there, it'd be well worth it. You can search for free online ones, but the ones schools pay for are usually probe deeper and give better results.