Once I have everything online, I email the client to let them know their pictures are ready to be viewed. In that email, I encourage them to forward the link to family and friends. Early on, I was always surprised to hear clients ask if it was ok to show their friends. Now, I don't just assume they'll know it's ok. Instead, I let them know in the initial email that it's a good idea to do so and say something about how their friends and family will appreciate seeing the pictures too.
After every event (wedding or portrait) I select a few of my favorite images from my shoot and put those on my blog. I do it so that the first thing the client sees is what I select as the best of the whole shoot. It preps them to fall in love with the images. Then, at the end of each blog post, I have a link to the event on instaproofs where they can see everything and make purchases. The link is, of course, available for anyone that reads my blog.
Deadlines make the world go around, so I always offer a 20% discount for the first three weeks the images are online.
I used to only keep the events online for about three months. Now, I keep everything online for 9 months. I want my list of events to be as long as possible. Why? When potential clients visit the instaproofs site and see a long list of events, they'll know I've been busy. It's the idea of social proof. People are more comfortable purchasing a product or service when they see that other people just like them have already done so.