Hi Bill and Marry, one of the easiest and better ways to fix this would be to dig a long trench starting from the wettest area to the lowest area of your yard. Go to Home Depot and buy as may bags of 1/2 to 3/4 stone you think you may need. Dig the trench about 12 inches wide and about 12 inches deep. Lay a thin layer of stone first. And then with a 4 inch perforated white drainage pipe you can buy at Home Depot, install with the holes facing down and then cover with stone about 2 inches think. Making sure the whole time that you keep a slope on this plastic pipe towards the lowest area of your yard. Make the end that it's able to to stick out from the ground. And make sure the beginning of this run has a cap on it. Cover back up with dirt and your done. Instead of stone you can use a landscape fabric, this much easier to use. The hardest thing about this job is the digging..
Also instead of caping the one end you can use a 90 degree elbow with a catch drain, something like your shower drain. And taper the ground down so it slopes towards the drain. I hope this helps you, if you need any more help please just ask me.
