In order to be able to pay your merchants, you'll need to enable mass payments on your Paypal account. To get this set up, you only need to take a few steps!
Step 1: You'll need to phone Paypal to have them set this up, so either grab your closest phone, or jump on Skype (or your favourite internet phone service).
Step 2: Go to the Help and Contact page at Paypal: https://www.paypal.com/ca/webapps/helpcenter/selfhelp/home/
Here you'll click the phone button on the right, and be asked to log in to your account. Once logged in, they'll give you a phone number, and a code to provide when you call in.
Step 3: Follow the phone prompts until you are able to talk to a human operator, and then simply ask them to enable the mass pay feature for your account. They'll get that set up on their end, and then you're all good to start paying your merchants!