1. Speed Dropping pages is great because it goes as fast as you can go and it's easy to get started, but it's bad because there are a few bumps in the road using this method.
Be prepared for these small setbacks with the speed dropping method; Some people don't have fast loading pages, their EntreCard isn't above the fold (don't have to scroll down) on their page, there's not an active ad on their page, in which case clicking their ad will take you to the site you're already on, and lastly you have to close out the previous windows or your computer may start going slow. Just watch the video though, it's pretty fast.
2. Bookmark pages that load fast with their Entrecard positioned near the top of their page, then revisit them each day for quick "card drops" so you can earn quick credits. Here's a fantastic list of Entrecard users with their card "above the fold."
Eventually, you will likely read some of the blogs too and possibly become interested too, so you will benefit in more way than one. Those same people will also see that you're dropping cards on them often, and may return the favor, boosting the price of your advertising space. Eventually someone will be buying your Entrecard ad space for 100 Entrecard credits, and you wont have to drop as many cards to get credits.
While many people (including myself and most of the links below) return "drops," some people put a blog badge on their site to make sure people know they return drops. They call it the "u drop i follow" movement. You can find a lot of sites and even get your site added to the list here. Keep a look out for logos like this:

Some "above the fold" sites that load fast to get you started with bookmarking are
- How Panties Define Us
- EntreCard Tips (this one, of course!)
- David Rader
- Swollen Pickles
- Cool Sites
- Pro Gamer
- Digital Burn
- Aussie Car News
- Guitar FX Depot
- The Comicologist
- The Staff Room
If you're using FireFox, you might want to check out this bookmark list to import!