I suggest if you plan on downloading frequently, to purchase a subscription to the site. But if you plan on downloading every so often, or if it is your first time, I have put together a little guide to help you navigate.
Obviously, in order for Uploadstation to offer free hosting, you will have to navigate through a few ads if you do not have a subscription.
Step 1: Click on the slower download button highlighted here
Step 2: Enter the Capta Recognition passcode
Step 3: Wait the determined time (usually short).
Do not be fooled by the "download with idownloader" button
Step 4: Click the "slower download" button and select the path to save your file
And there you go! You will be getting your royalty free files in no time. Later I will go into detail how to automate the downloads a little more using programs like Jdownloader.
Feel free to ask any questions you may have, I will try my best to answer as many as I can.
Thanks for reading.