Keep an honest and thorough food and exercise log. Use an online app if that helps. I use a free one called lose it.com.
Change up your exercise routine. If you mostly walk, try swimming. If you mostly do aerobics, try some strength training.
Change out your protein sources. If you eat a lot of beef, try fish. If you eat a lot of fish, try dairy or soy.
The idea is to wake up your metabolism and make it do something other than the usual routine. Sometimes adding a couple hundred calories to your day can convince the body it is not being starved and can let go of the stored fat.
Congratulations on your progress. Remember to acknowledge what you've done so far. It isn't easy. I just pushed through a plateau of my own. Tracking my food told me too many carbs were sneaking back into my life. I cleaned them out of my life again and went back to the basics that work for me.
The scale has started moving again.