Create Facebook connection and sharing platform through site

Hi, I currently have a landing page for a competition which forces users to Share a post to be able to get through to the next step of the website. I am looking for somebody who can come up with a better idea and implement how to connect a user through facebook and make them share the post. -Is there anything more we can do with the user that connects? - Can we automatically post for them in the future? - Can we automatically post on there wall if they connect, instead of having to share and be aware of what is being shared? I want some other alternatives to connecting my new users entering the competition. The goal here is to get each user to share my landing page but i find a lot of people drop off as they see what they are sharing and prefer not to. Please message me with what you can do to optimise the best? Thx