Post regularly, several times a day, various content - viral videos, images with with clear and contrasting colors, links, questions; join different relevant groups on FB and post there. Use Facebook paid advertising, find out who is your target audience and advertise to them. You'll get active likes this way.
I agree with previous post. There is no other effective way to earn more likes that you have now.. Ofcourse you can by likes and reposts, but usually such platforms have accounts which are not looks like live accounts of real users and it looks a little spammy. Moreover, they repost a lot of other pages, so I think you also can be banned because of them..
Huge numbers of Likes can come naturally in almost any industry provided you are offering regular, intereresting and relevant new posts. It may take some time to develop a large enough audience to naturally generate Likes so one trick is to Like others, similarly themed Facebook Fan Pages. Often, that is enough to encourage those players to visit and in turn Like your page.
Hm..I though that you can be banned for such actions and if algorithms of Facebook reveals such activity moreover if you will have a lot of outgoing requests to add as friends, I think It will implement sanctions.. no?