Web Page Template

I have 4 videos, that are about 2 minutes each. I want visitors to watch all 4 videos to qualify for a discount coupon. They must watch all videos in order, I think the best way to do it is to have a button appear after the video is complete, below the video instructing them to "click here" to watch the next video.... After the last video they will be taken to a form to fill out with some qualifying questions, then taken to a Paypal payment page. I can create these pages if you just send them there after the last video but with confirmation... I have a template that I am using and started, but need help with making a button appear after the video is complete to watch the next. Plus all this is in php and I don't know php... [login to view URL]