To start a free test, you just need to select the Karma option when you are setting up the test.
By giving your opinion (voting) on other people's photos, you earn feedback on your own.
As a timesaver and to get more feedback faster, there's also the option to buy Credits instead of voting.
You earn Karma by voting here.
Your Karma level can be low, medium or high. Every time you submit a vote, you'll notice a progress bar appears on the vote button.
This bar shows you how close you are to reaching the next Karma level.
The more Karma you earn, the more votes you can expect to receive on your own Karma test.
As your own test collects votes, your Karma gets used up, but you can vote again to to raise it.
Credits are purchased, not earned through voting.
Tests using Credits receive votes faster and get a guaranteed number of votes. Additionally, using Credits, you can run multiple photo tests at once.
The exchange rate is 1 Credit spent = 1 Vote received.