Dare I say it: Choosing college classes is not rocket science. First decide where you want to go. Then take the fewest classes that will get you there. If you still need extra units to graduate, do a survey of people who are working in the field of study you are interested in. Ask them for the elective courses they took that might be of the greatest utility. By the way, the results of this survey may surprise you. For instance, computer programmers or database designers might tell you that a class in basic or abstract logic was the most useful to them. Some scientists and engineers might reveal that a course in technical writing was the best use of their time because it turns out they have to write and review reports all the time. Almost any professional might tell you that a course in public speaking is something you will never regret. And still others may tell you that a class in art, drawing, or computer assisted drawing put them heads and shoulders above their competitors because they could show the idea they wanted to sell visually.
So your first order of business is to pick a major. Get some use out of that high school counselor. Sit down with him and talk about the things you like to do, the things you don't like to do and what you could end up doing. Try to get into some internships in various industries so you can get a feel for the kinds of work you might like to do. Do some traveling and see how other people live. Survey all your parents friends and all your friends parents. Ask them what they do for a living and why. Ask them if they like their jobs and why or why not. Use all this information to make an initial assessment and pick a college major.
Go to the course catalogs of three or more colleges that you have chosen. Look up the major you are thinking about and look at the course of study required to get there. Eliminate colleges that don't teach what you want to major in. Eliminate colleges that are not accredited in what you want to major in. If you still have more than one college to look at use Google to find which college has the best reputation for the field of study you want to go into. You have chosen your college.
Return to the college course catalog. The courses you need to take will be laid out in sequence. Take as many of the first year courses in the sequence as you can handle. Check to see when the subsequent courses are being offered. If one of the upper series courses is only being offered at a particular time of year then you must ensure that you complete all the prerequisite courses first. So first find all the courses that are only taught at specific or rare intervals. Now plan a course of studies that will get you all the perquisite courses before the hard to get course is offered. Finish the lower ones then take the rare one.