You could always create your own OFP mission download WEB page somewhere and brag on the forums about it. However, unless you're an already well known mission maker, your claims will often be ignored and few will bother downloading your missions.
So, if you're really that good, here's a better idea! Several of the sites listed in this FAQ item allow you to submit your mission files to the site's mission database for downloading, reviewing and ranking by OFP players worldwide. My I suggest that you submit your missions in compressed ZIP file format.