In reply to Removed Userlfenbo: Agreed with above. If there is an issue with the brake (warped disc etc) that can't be sorted by adjusting, its better to take it back.
Turn bike upside down and give the wheel a good spin, you should see the rotor spining absolutely true. If it is and you really feel like tinkering with it yourself.
1) find out where its touching from, get a torch to help you.
2) find out (before undoing them) which of the bolts will need to be undone to adjust it in that direction.
3) undo the those bolts until the caliper can be moved, but not so much that its floppy.
4) rotate the wheel checking for rubbing (noise)You can also check this by sliding a paper in the gap too.
5) gradually tighten the bolts carefully and still checking for the rubbing as the caliper may move slightly as you do this or adjust inwards. correct this if necessary as you go on tightening.
If the problem is more serious then this (i.e. rebleeding brake or facing the mounting on the frame) then definitely take it back.
Hope this helps... oh and happy riding!