How to install Elements 12 on MacBook Air with no DVD drive? [was:URGANT HELP NEEDED!]

I have a MacBook Air, with no CD drive. I just purchased 'Adobe Photoshop Elements 12 & Adobe Photoshop Elements 12 Premiere', from the 'Best Buy' store. I asked for help before I purchased the product, to make sure I did not need a CD drive to download 'Photoshop' to my MacBook Air, the lady told me I did not need a CD drive for it to download. I come home to download it, to find that there are no instructions for online downloading or downloading without a CD drive. I have tried calling customer service and doing research on the computer for help and I can not find any answers what so ever. I really need help with this, as I have deleted all of my photos and videos on my MacBook Air to free up enough space for 'Photoshop' to fit on my laptop. Please help AS SOON AS POSSIBLE, thanks!

-Savanna Follari