"Sure, it's important to you, but why is it important to me?"
Whether they realize it or not, that's what's going through their head when you ask them for referrals.
Why would people give you referrals? First, is what you have to offer worth offering? We are literally exposed to thousands of brands and services every day, what makes yours so incredible? Start there, because maybe it's not...maybe there's something you need to change.
Second, make it easy for someone to bring up what you do. You do this by being incredibly generous with your marketing efforts. Free content, clever packaging, making it specific and relevant. Then, of course, it's easy to bring something up when it's already helped you. You're wearing it, you benefited from it, you use it (or go to it) every day.
Finally, be the type of person people want to work with. There's a reason why software companies invest so much money in salespeople. They may be selling machines and robots, but it's the relationships that matter most. Be deserving of people passing your name along, whether they are or aren't; if you do the right thing, others will eventually notice.
The easiest way to help people understand that you are worthy of their referral is to tell a story. Be someone they can relate to.
The best way to get people to refer you is to back up your story with admirable action.