The absolute BEST website for creating your QR code is azonmobile.com's QR Code Generator, HERE.
The first option is choosing what you would like your QR code for... You can make them so that when they are scanned, it opens an email addressed to you, you can make them as a written (text) message, plus many more options.
In this instance though, we would want your website URL (as below).
Your next option is error correction, this is how much give and take your qr code has in regards to it being read. The higher the error correction, the better it will find your site, but the more "blocks" will be on the image.
The default on this site is "Medium-High". This is a good selection.
The next two options, "Block Size" and "Border Size" are better left as is.
Block style is great to play around with. You can make them Square, Rounded (rounded corners only) or Circular (Bubbles).
Foreground Colour is the colour of the blocks in your code. This is denoted by a Hex Colour Code, visit the link for a colour picker and link to a very comprehensive list of Hex Colour Codes. Alternatively, below this you have the option of using an image which is cut into to create the blocks for your QR code image.
Background colour is the same option, either a hex colour code or background image is usable. For my code above I used part of my blog's background image.
Finally, you can emded an image (like your logo image) into the QR code! Very clever if you ask me! This image is placed in a space in the center of your QR code image (which is what I have done above with a "D", for Design du Jour), unless you select the tick box marked "Overlay the logo". This option will place the logo over the entire QR code image.
Finally, by clicking Generate (as in the image below) it will display your created QR Code image, plus the option to download your creation, for use on your website!
Thanks for stopping by and if you have any questions regarding this or anything else on my site, please comment or contact me via the links to the left.