When should I take the SAT/ACT/subject tests?

<p>I'm a Junior in high school and I'm feeling really stressed out trying to figure this all out. I want to take both the SAT and the ACT, and I'd like to take both twice, once on my own without much prep just to get a feel for them, and then again after some hard-core studying. For the ACT, I plan to take it in February and then again in June. For the SAT I'm not really sure. The second time will most likely be in June, but I'm not sure if I should take it for the first time in January or March (if I pick January I need to sign up soon). And then there's the whole SAT subject tests issue. Some of the school I want to apply to want at least two of them. Most say they'll take the ACT in place of them, but I don't know how I'm going to score on that. I have an idea of how I'll do on the SAT because I took the PSAT and scored a 191(0). So long story short I do feel like I should take a few subject tests. I'm planning on Literature, Math I, and either US History or Chemistry. Should I take these in May? I feel so overwhelmed trying to figure all this out.</p>