Building a single page compatible for Mobile - where to start?

Question

I\'ve got a site that isn\'t mobile enabled, but as part of a campaign, we are going to be sending out a QR code that contains a voucher to link through to a \"hidden\" page

Answer 1

My question is, how do I go about doing this?

If you want to use the same page for regular size displays and mobile size displays, then look at media queries so you can do adaptive design (for which mediaqueri.es has some examples.

Whether or not you want to adapt to display size, the only other major factor is testing. Make sure you test on a range of devices and browsers.