You have 30 moves to drench the board. Go drench it now. Drench it!
Confused? Don’t be. See the colour of the square in the top left of the board? That’s where you start! Clicking on a colour in one of the circles on the right, changes the colour of that square (the top left one, remember?). When that square becomes the same colour as a neighbouring square, changing the colour (by clicking on a colour on the right), changes the colour of the entire group. Yes, I’m making it sound more confusing than it is. You’re better off just experimenting for yourself. What you want to do, is always make the colour selection that is the most beneficial for you – the choice that nets you the most additional squares, or gives you access to the most in the next move.
You’ll pick it up in no time, I’m sure of it.