I think the road map will be different for each family and what they feel comfortable with.
For us, I always wanted my kid to devote her full energies to school while school was in session so she could get the most out of that experience that she could. I’m not just talking about academics, but also the extra curriculars and the social aspects too.
So that meant that I tried to get her to do all of the college related work during the summers or other breaks, which meant that we started very early. For some families, starting early results in a pressure cooker, but for our family, this actually took pressure off and let her enjoy HS more.
What this looked like for us is that our D studied for the ACT during the summer after Sophmore Year, and took the September (October?) test Junior Year. Luckily she only had to take it once, but if she had to take it again, I would have had her study over winter break and retake then, and then study over the summer and retake early Senior Fall. For the SAT2s, our family’s experience was that it was fine to take it after bio1 after freshman year. Your boarding school GC should be able to tell you if the kids at your school typically take this test after freshmen year and how they do. Also, I’m sure somewhere on your boarding school’s website there is a link to a pamphlet about your BS’ profile, and in there it will show how many kids took which subject tests last year, and how they scored. For example, in our school the physics teacher was phenomenal so a high percentage of the kids at our school took the physics SAT2, and the average score at our school was a 780. Well, this gave us a pretty good idea that if our kid wanted to take physics, this was probably a good SAT2 for her to take. Likewise, we saw that the average for the Spanish SAT2 was relatively low, so absent other considerations it was probably a good idea not to take that one. Also, with regard to the SAT2 timing, most kids take it Junior Year right after the APs in May. My D waited until June, and I think that helped a lot. The kids are just too tired in May with the AP and all the year-end performances and games etc. Most SAT2s (particularly US History) are slightly different than the AP, and your kid should spend a little time looking at the format and studying for it, and the extra couple of weeks really helps IMO.
As part of preparing early, you need to make yourself aware of what the current admissions situation is. Even though grandpa thinks your kid should go to XYZ school, the admissions chances are so much less now than they were even a few years ago. Start preparing yourself and your family for this new reality, so they won’t pressure your kid with unrealistic expectations. Also, you may have chosen your BS in part because they send X # of kids a year to Ivy League schools. Well, you need to look behind those numbers to see if your kid really has the same chance as the kids who got in. For example, if 3 kids from this year’s Senior class go to Yale, and 2 are athletic recruits and 1 is a legacy, and your kid is neither, well, how many other kids from your BS applied to Yale, who were they, and what were their results? I’m making this a bit too simplistic, because there are nuances for everything, but I do think it’s safe to say some kids will have an admissions advantage over others because they fulfill an institutional need, and you should look to see if your kid will also fulfill an institutional need or falls in the general population of applicants. Your GC should know all this information and should be able to really help your child pick appropriate schools, so if you’re not able to figure out the story behind your BS’s college admissions that should be fine; I just know that I really appreciated seeing this information for myself.
And, you need to look beyond the same old schools that everyone from your BS applies to. There are some truly excellent schools that aren’t on your radar yet. A little reading now will help you know which ones might be good for your child to visit.
About visits, our family started college visits during our D’s sophmore year when she had school breaks. We were glad we did, because Junior Year was too busy to take time off during the school year, and same with Senior Year. Senior Year Fall my D did take a second visit to two colleges in order to verify she was ready to apply ED to one of them, but she had to miss an important EC, thereby reaffirming how happy we were that she did her other visits during non-school times. Also, while a lot of families will say that summer visits aren’t good, we still found value in them because there were nuances in the info sessions that helped us realize what that school valued.
Besides all the above, our 4 year plan included having our D do things over the summer that would help make her an interesting person. This was for her own growth as a person, and not directed at what would look good for a college application. While these experiences can be an expensive science camp if that leads to something interesting and of value, or it can be studying abroad to learn a language, it can also be volunteering in a science museum and getting involved with something they are doing, or volunteering to teach English at a church or library ESL program. It just has to be something that interests your kid and speaks to them, and is something that they can make theirs and do something with. Our GC actually recommended against expensive experiences because it smells of privilege that isn’t available to everyone, but I think it’s OK as long as your kid is undertaking the experience with a specific goal in mind and does something with the experience, rather than just being a spectator going from one expensive thing to the next.