The steps are simple, but podcast promotion is not easy.

1. Know who your audience is
2. Make GREAT content for THAT audience. Content that leaves them going "WOW I've go to tell my friends about this."
3. Go to where that audience is.
4. Make friends with them bringing value to every conversation.
5. Tell them about your podcast. (do not swap 4 and 5, they won't care about your podcast until they care about you).

If you're looking for the giant switch that gives you 10,000 downloads it doesn't exist. Other things that will speed things up is doing interviews and having those people promote their appearance.

Last never say the word, "only." As in "I only have 67 downloads." Those are people who chose your content over thousands of others. If this was a school 67 people would be 3 classrooms if not four.

As for tools, twitter, facebook, google+ (look for groups in Google and Facebook), meetup.com for in person meetings. You build your audience one person at a time.