I've seen a ton of questions on here about backlinking such as where to find backlinks and how to determine whether they are quality or not. One method I've found to both find backlinks and make sure they are quality is called the copycat method. This method is pretty simple as you'll be examining your competitors who rank on the first page and their backlink profile. Once you have a list of their links you'll be able to pick and choose which you would like to take and implement them for your own site. Now the reason this works so well is that you'll be given a wide variety of links depending on how many competitors you view and the way you can double check the links are quality is that your competitors have not been hit with penalties and rank on the first page normally indicating strong and safe links (usually). It sounds pretty simple and hopefully many people already use this strategy but if not hopefully this helps.