A process definition can be designed as normal with steps and connections such as shown below:

According to the design of the workflow, once each task is completed, the process navigates to next task.  But let’s say that you want to jump from Task1 to Task3.   Just use the jump functionality, select the workflow instance and use the following menu option:

Make the selections using the following dialog:

Once you click the “Jump” button, the workflow will get processed and will render as follows: