If you've ever see late-night television infomercials from the likes of Billy Mays or Andrew "Sully" Sullivan, you would have noticed that there's always a "but wait, there's more!" offer for every product. There's a reason for that and it is because bonuses work, and work well. Consumers often get triggered into buying something, anything, when they feel like the deal is too good to pass up. That's why it's important for you to always have some type of bonus offer included with anything you're selling.
A bonus offer can be anything. It could be a free month of service. It could be a training DVD made up of videos you've done in the past. It could be an ebook you've written. It could be access to a private forum or community. The point is that it's a bonus. It's something that the buyer wants, not something thrown in that is unrelated. Resist that urge to add a ton of unrelated bonuses. Instead, make your bonus item almost as valuable as the main item you are selling. That way the customer feels like they are getting a deal too good to pass up.
Every time you go to sell something online, make sure you have a bonus item of some type to sweeten the pot.