Know-How Exchange : Strategy

You charge people to participate.

You spend less than you take in.

Advertising.

Typically these types of websites don't make a lot of money at first. You have to build up popularity and get a decent amount of traffic to your site first. From there you can sell advertising space to companies marketing to the demographics your users fit into.

You can also charge people to participate as Inbox_Interactive mentioned, however most people will not pay until you've developed a good reputation for the site. It should start with a trial account for users to participate for free and once there are enough people involved you can move memberships to include a fee.

Though not very politically correct, a key to making speed dating money is to realize you have different groups of customers, for which your site is more valuable than for others. This has been called 'dual platform', with Ebay as a great example: only sellers pay fees, because the site is more valuable to them. In contrast, buyers pay nothing because Ebay needs them to convince the sellers to pay fees. Of course, Ebay needs sellers too (otherwise buyers have nothing to buy), but it offers more value to the seller than vice versa.

So in your speed dating website, who are the buyers and who are the sellers? Build an attractive, free and easy-to use website for the buyers and keep it free for them. For the sellers, work with free trials etc but once you become the key game in (digital) town, charge them