When processing applications, universities must match your info from multiple sources - transcripts from e-transcript or schools; scores from testing agencies; online applications from students. When students use different versions or spellings of their firstname, the task becomes complicated and may delay application processing.
Tip #1: When registering for SATs, colleges, etc, use your name as it appears on your high school record.
Tip #2: Use the same email address throughout your college search. Schools often use the email to match material to a particular student.
Tip #3: Never use your AC email for applications. It cannot receive emails colleges might send you once you graduate.