This work presents some techniques and tricks of visualization which can help us with certain types of problems from elementary probability theory. The emphasis is on systematical solutions of the problems and the way how pupils can visually set the task and then relatively easy read off the results. The first technique of visualization is the Venn diagram in which events are treated as sets. By using them, we visualize the algebra of sets and we are evaluating the probability of an event by reading off data from the diagram. Furthermore, the two-way tables can help us with simple problems with several events, but also with visualization of independence of the events. There are some examples of construction of tables from which we can read off data in order to calculate the probability of some event. The most useful trick of visualization of probabilities is a tree diagram which can help us with more complex problems concerning conditional probabilities, but also for the discovery and understanding of the Bayes theorem. Therefore, we provide some examples of activities how pupils can reveal the structure of the tree diagram by themselves and then read more complex probability from it. In the end, the idea of a geometric probability is actually reducing probability problems to calculating areas of different shapes. That is a standard trick in solving the problems in which the space of elementary events must be uncountable. Besides various examples of solving tasks with geometric probability, we also specified an example of the activity that can be used as a motivation for the discovering of geometric probability during the teaching process.