As adults our tendency is towards delaying asking for help. By the time a student has asked for help chances are good that they have already tried several different things. Find out exactly what it is they are trying to do. Help them to recall as many steps as possible. Then verbally explain how to get back to where they started and guide them to perform the task they were attempting.
Experience is the best teacher.
Give instructions in no more than 3 instructions at a time. For example point to the Icon, double click on the icon, select mail. Explain to your students what you are doing, show them how the operation is performed, have them do it together as a group. Build small exercises into the curriculum. Do not give new information or ramble about personal experiences.