1. Pour your brown beans into your tub or bowl. These represent the wild animals in the habitat which you are studying. You have "captured" 30 of them, and are about to mark them and return them to the population.
2. Count out 30 white beans and add them to the tub. These white beans represent your initial capture. You have marked them by "painting" them white so you can distinguish them from their brown fellow beans.
3. Cover the tub securely and mix the beans as thoroughly as you can. Thorough mixing is vital to the accuracy of your estimate
4. You are now ready to begin your sampling. Since chance affects every recapture you make, you will repeat your recapture 20 times, calculate the estimate for each recapture, then average the 20 estimates.
5. Here is the procedure for each recapture:
   1. Without looking, reach into the tub and remove a handful of beans.
   2. Count the total number of beans in your sample and record this number on your data sheet (n).
   3. Count the number of white beans in your sample and record this number on your data sheet (t). Each sample must have at least one white bean in it; if it doesn't, throw it back and repeat the sampling.
   4. Return all of the beans to the tub, replace the cover tightly and mix thoroughly.
6. Repeat this process an additional 19 times. You are now ready to begin the calculations.