Once you have several solutions, evaluate them and discard the unacceptable ones. This step will require time and honesty and may require negotiation.  Talk about which solutions will work and how difficult they will be to implement. 

Set aside your opinions for a moment. Understand and acknowledge all points of view. Sum up those points of view in words that the other parties can accept. When people feel they’ve been heard (acknowledge), they’re often more willing to listen.

Brainstorm and dream up as many solutions as you can. Don’t evaluate them. Quantity, not quality, is the key. If you get stuck, restate the problem and continue brainstorming

Implement the solution - decide who is going to do what and when. Be clear about everyone's roles and the expectations. 

Evaluate the solutions that you come up with.

Review the effectiveness of the solution. If it works, pat yourself on the back. If not, be open to making changes or implementing a Re-evaluate the solution. Either way get feedback. Even good plans can be improved upon for next time. 

Use “I” messages to explain your perspective of the problem and allow the other person to do the same. This is important as you may have different problems or different perspectives on the same problem.