@beccaW444. I would strongly recommend you start a list for each school you are applying to whether you create a spreadsheet or write it in a notebook. Then write down all the necessary info and dates for each school. Some will have you apply before you send in a prescreen. Others will tell you to apply if you pass their prescreen. Some don’t have a prescreen at all. Some require extra essays. Some do not. Some accept the common app. Some do not. All of them will give specifics on their website. And if you don’t see what you need or dont understand the directions, contact the MT department and clarify with them. But you have to do your homework for each school. They are all different.
You need to have your headshots to send in with your applications as well as to take to auditions. So depending on when your senior pics are being taken, they may or may not work. Also make sure they are appropriate for a headshot.
I would recommend reading Mary Anna Dennard’s book called “I Got In”. She goes through the entire process of what to do nd when in a concise easy to read manner.
@BeccaW444 - do you have a list of schools you are applying to? Perhaps there are some folks on CC applying to the same programs who might share critical dates with you. Regardless, this process is nerve-wracking and there is no way around checking the nit-picky details for each program you are applying to. If your senior pictures are not done in time for your deadlines - or are not appropriate for headshot purposes - and money or time is an issue, you can have a friend/mentor take the picture for you. Just be sure it is well lit with a plain background. You can google “theater headshot” for examples and how-to. You do not want something that looks like a “glamour” pose.
@halflokum I didn’t actually think of it myself. My kids attended a K-12 school and the first time they took the ACT they were in 6th grade (they took it through a gifted and talented program). They told us to make sure we did NOT put the school code on there because we would not want the school to inadvertently report a 6th grade score to colleges in several years. A discussion ensued among parents and we realized that we could just use the homeschool code until we were satisfied with the score. My kids took the ACT in 6th, 8th and 10th grades. They considered that all the study/practice/tutoring they needed 
Many, many years ago when I was in school and took the ACT, I took it twice. I thought you had to report the scores to three colleges because there were places for three codes. I was afraid I would do worse the second time so I picked three colleges that I had never heard of to have my scores sent to. Then when my scores improved, I paid to have them sent to my school of choice.
@Dusing2, smart… even if you didn’t invent it. My kids both took only the ACT (not the SAT) in junior year but our paranoia about not knowing the scores lead to us not using the “free” (so funny… didn’t we pay a fee?) schools at all and hitting the trigger after the fact. It never dawned on me that their scores might be on the HS transcripts. I assumed we were entirely in control of that info and I wasn’t on the lookout for that. Turns out it didn’t matter because their jr year scores were the ones they went with but if I were doing it over, I’d put a wall up around the whole transcript thing because I do feel like that it is the student’s privy to decide where that info goes and I had no clue whatsoever that the HS could jump that.