Don't be afraid to promote your comic. The comic creator who doesn't p[romote is the comic creator with no readers. Sorry, all of you who want to be humble, it doesn't work. You need to tell people about your comic. If you aren't a featured comic, you're relying on luck for people to stumble upon it out of the literally thousands of comics out there.
So, first make sure you have enough content to interest people. Don't invest massive energy in promotion unless you have something to catch the interest of readers.
Promoting on the forums is good. Participate and mention (with a link) your comic when it's appropriate to the discussion. Get on social media and start building your network. One in five posts can promote your own comic without feeling pushy. Otherwise, just participate in the discussions, be interesting, search for contacts who might be interested in your book.
Be inventive, be proud, try not to be too pushy. Building an audience takes more then a great comic, it takes work promoting it. Yes, you MIGHT get lucky and just be popular and take off, but for most, luck is not enough.