Essentially just be active and stay on top of news. Don't wait until someone has already gotten too much press, on a bad team you likely have room to add players at will and not worry about who to drop. Maybe a guy like Chester Rogers for the Colts. Hasn't made too much noise yet but he may be the #3 guy in a good offense and 1 injury makes him valuable in a hurry. I picked up Taylor Gabriel off waivers last year and in some leagues got a 2nd, others still have him. You'll get a lot of duds but you didn't have many picks so you need all the help you can get. Our waivers is open all summer so I'll add guys for 0$ bids to see how camp shakes out.
And during the season you can't afford to snooze. I signed up for football guys email list, it's free and they have lots of tidbits compiled to condense the information for you. If you get someone and their value starts to increase I always look to move them for a pick. Sure yiu have tines where you sell an Alfred Morris too cheap too soon but more then likely you'll win your fair share that way. No real specifics involved other then being active. Allen Hurns was another guy who people kind of slept on until it was too late, and now his value has bottomed back out again. If you can find just a couple guys like that a year consider it a win. There will always be a couple big injury adds nobody saw coming, just have to hope you allocated your funds and know when to strike.