Exam

It is not necessary that applicants upload their photos right in the first go of SAT registration. Applicants can come back after paying for the SAT exam registration and still upload their headshot photos. Also they must note, that they must upload their photo at least five days before the actual exam date, following the phot requirements, else they will not be able to give the exam. 

Uploading your recent photo is essential before you sit for the main SAT exam. The definition of a good photo as per College Board is as follows:

• The image must be in any of these formats - .jpg, .gif, or .png.
• You must be recognizable in the photo you upload, basically the headshot must be clear.
• The photo should not be too dark or too light.
• Ensure that the eyes are open and not closed.
• Photo must be natural and must not be altered using any tool.
• Finally, the image must include only you and nobody else.

If these instructions are not followed, then you may not be allowed to appear for the test. 

Yes, it is mandatory to get the One-Time Registration (OTR) Number before applying for the SSC CGL exam. The candidates require OTR to login at ssc.gov.in. Without One Time Registration, the candidates won't be able to login and hence no application will be visible to them. OTR is independant to the exam, and the candidates can apply for any number of SSC exams with one OTR only.