The force field analysis lists forces against and forces for a certain alternative and sums their scores.
You could also exchange forces against and forces for with disadvantages and advantages of a certain alternative. In a group setting, a force field analysis can also uncover who are resisting or assisting a certain alternative and in that way already prepare for implementation.
Executing the Method
For each alternative or idea, generate forces against and forces for this alternative.
Score each of these forces with a numerical value, preferably on a 1-5 scale (obviously, negative scores for forces against).
Sum these scores to get a combined score of the alternative, and decide which alternative to pursue based on the total scores of each individual alternative.