The best thing to do is visit poea and approach one of the windows on the left side upon entering the premises.(unless they changed offices) you may want to inquire abt your interest to apply as a nurse in KSA. They are very helpful. They would give you a list of requirements to accomplish and would require you to submit two sets of the said requirements in a chronological order (I mean according to the list). That would include your resume with job descriptions, otr, trainings, college and high school diploma, sets of 2x2 pictures. (but please refer to the list they would give you)
KSA could be a good training ground with pay rather than serving as a volunteer nurse in the phils ( this is just a personal opinion).