Give more attractive and informative posts. Also join in groups depends on your product or service, increase members from the group then your likes will get increased automatically. Or else promote your page.
you can do many thing to promte your page first of all you can use picture and videos specily to promote your page .. use uniques and attractive pictures and videos to attract people to your page.. more share you will get more like you will genrate.. Or you can use any exchange site to get likes.
Try to increase your social network in facebook or in other sites.
Now a days on web there are lots of tool or sites through which you can more than 100 likes per day but that all likes are useless for the business purpose. So just interact with genuine user and invite them like your FB page
IIf you want quality pratilce, you have to do fb ads or groups to leave comments and there will be people who are interested.
I do not recommend that you use FB like exchange, because most are poor quality characters, mostly to farms like
share interesting posts, promote your posts by paying a small amount now and then, run contests and give away prizes for your fans, join communities within facebook and outside for like exchange and share likes with limit frequently
Some of the ways to increase a facebook likes are:
1) Facebook contests are the easiest way to get people excited and draw new users in as Fans.
2) Like-Gated Coupons-Coupons are a great promotion. Something small like a 10% off coupon gives people an incentive to buy while keeping your margins intact.
3) Like-Gated Ebooks- Sometimes educational content is a better incentive than a discount offer or prize, depending on your industry or target market.
4) Facebook Ads are the easiest way to increase your valuable Facebook Likes. Why? Because you’re guaranteed visibility of your brand to a highly targeted audience.
5) Add a “Like” button or box to your blog.
6) Add a “Like” button to your Website’s Header.
7) Exclusive Like-Gated Videos
Start submitting the topics which are of the current trends and look for the groups of the same category and like them then your post automatically gets highlighted in their's. Through this you can increase your likes.
also check the quality of the likes you get, coz you might have 5 million likes of people who dont really want your product.
a very important factor on facebook pages is user engagement how do users engage with your content that you post