INSEAD really looks for those with GRE scores in the 75th - 80th percentiles as a minimum, which means your scores are way off. Your quant should be at least 720 and your verbal at least 540, or a composite score of at least 1260.
As for your experience - INSEAD adcoms really look for those who have spent significant time outside your home country (in your case, outside of Nigeria) living or working full-time.
In any case, what I suggest you do is see if you can retake the GRE, or do the GMAT (GMAT: shoot for 700+, and 680 at a bare minimum) and boost it to a score that is competitive. Beyond that, all you can do is focus on the written application and interviews if you really want to go to INSEAD.