Here are 6 primary tools at your disposal to get rid of weeds: 

1) Total weed wipeout with nonselective sprays or solarizing techniques

2) Spot weeding with nonselective sprays, flaming, or mechanical tools

3) Preemergent weed control in spring and fall

4) Soil modification that gets to the root of the problem

5) Overseeding with new grass seed to crowd out weeds

6) Mowing at appropriate heights and only occasionally using a bagging attachment on your mower