Dear Mohammad, using KEEL is quite straightforward. You just need to select the type of partition (usually 10 fold cross validation), the type of experiment (classification, for instance), select the datasets (KEEL has some datasets available, but you can import others, preprocessing algorithms, if that is necessary, then the main algorithms (classification, regression, etc), and so on. Check the User Manual tab for detailed information on each step. After the whole experimentation setup is done, save it, and follow the instructions to run the experiments. Hope that helps.