What is the process to get an OPT job?

The First Step is to approach your DSO and update your SEVIS.

One should be eligible first with the following criteria: Employment that a student takes up must be relevant to his/her major.
Legal F-1 status must be maintained by the students.
Students must decide, whether they wish to take up Pre-completion OPT (OPT while they are still in the University), Post-Completion OPT (OPT after graduation), or a combination of the two.
OPT application from a student must be completed before he/she graduates.
The period of part-time OPT is deducted from the available full-time OPT of a student.
A student who has completed Curricular Practical Training (CPT) for 12 months or more is not eligible for OPT training.

How to apply for OPT: For starting the OPT job search, a student must first receive approval from his/her Designated School Official (DSO) for pursuing his/her post-completion OPT. Upon this, a student must apply for an Employment Authorization Document (EAD) from the United States Citizenship and Immigration Services (USCIS) within 30 days. Moreover, a student must start his/her OPT application up to 90 days prior to the end-date of the program and no later than 60 days after his/ her graduation date.

Post-completion OPT Rules
In order to attain post-completion OPT, a student must follow certain rules. Following are the post-completion OPT rules:

OPT Students must work full time i.e., 40 hours a week.
Once a student completes graduation, his/her OPT work must be finished within 14 months from then on.
Post-completion OPT applications must reach USCIS before a student completes his/her graduation.

Check out online job portals like OPTnation.com.