Set up your running schedule. You will want to run two times a week for about 30 minutes and schedule one day (typically a weekend) for a longer run, going for distance rather than time. Work your long runs up to the distance that you need to run for your final race, and schedule about six months of preparation time for a marathon, four months for a half-marathon and two for a 10K.
Determine your goal time for completing your chosen race. Consider the distance of your "final race" (10K, half-marathon or marathon) and divide the time by the number of miles to determine your goal race pace. For example, if you are running six miles, and want to do so in an hour or less, then you will want to run a goal pace of a 10-minute mile.
Determine the Run/Walk/Run ratio that will work for you by using the chart below:
Min/Mile Run/Walk Ratio
8 min/mile 4 minutes/35 seconds
9 min/mile 4 minutes/1 minute
10 min/mile 3 minutes/1 minute
11 min/mile 2.5 minutes/1 minute
12 min/mile 2 minutes/1 minute
13 min/mile 1 minute/1 minute
14 min/mile 30 seconds/30 seconds
15 min/mile 30 seconds/45 seconds
16 min/mile 30 seconds/60 seconds
Utilize the Run/Walk/Run schedule referenced by the above chart. To meet your approximate race time, you will want to run for the suggested time, and then walk for the suggested time. Use a stop watch during your runs to time the segments.