Choose your season. There are only two - dry season and wet season, which correspond to high and low tourist seasons. The high/dry season runs from early May to late October, when the prices of everything, including airfares and accommodation, will be at their peak. Opting for the low/wet season (November through April), when there will be plenty of sunshine (just not as much), allows you to take advantage of lower prices and smaller crowds, although visibility for scuba diving isn't as good when skies are overcast.
Research airlines. Go online and type "flights to tahiti from u.s." into a search line. To reach Bora Bora, you have to fly to Faa'a International Airport in Papeete, the capital of Tahiti, and from there, take a boat, plane or helicopter. Many airlines, including Air France, Delta, Hawaiian and Air Tahiti Nui, offer scheduled flights to Tahiti, most departing from Los Angeles. Fares are competitive so if you're not going to save any money by choosing one over the other, find the best value by typing "airline quality ratings" (without the quotes) into a search line.
Read travelers' reviews. Gone are the days when travelers have to rely on tourist boards, tour operators and travel agencies for information about what a destination is really like. With the Internet, we can now get honest opinions from ordinary people who don't make their living from tourism promotion. If you have your heart set on Bora Bora, it is especially important that you get the straight goods about the place from people who have been there because despite its mystique, many visitors say it is overpriced, overhyped and overdeveloped. An excellent website for candid opinions and impartial reviews is www.tripadvisor.com.
Stay flexible. Bora Bora is among a group of islands and coral atolls called the Society Islands, legendary for their beauty and easily reachable by boat. The others are quieter, less developed and cheaper. If you're interested in a more low-key vacation experience, investigate the possibility of staying on a neighboring island and visiting Bora Bora from there. Type "French Polynesia" and "Society Islands" into a search line to explore your options.