How to preheat convection oven

Before you bake something, your oven needs to be heated to the proper temperature. While it takes only a few seconds to turn on your oven, it can take several minutes for it to reach the right temperature.
The first step to preheating an oven is to turn it on to the temperature you want it to be. In old oven, this involved turning a dial. In modern oven, this involves hitting a few buttons.

• Open and check the oven to make sure everything is removed. (I make the mistake every time so I am mentioning it).
• Rearrange the racks if  needed.(For some recipes we have to use upper racks and for some lower racks)
• Check the preheat level required by your recipe. Turn on the oven by pressing on bake option and set it to the correct temperature by using + or - buttons. 

• Wait until the oven reaches the desired temperature before placing food inside. Most modern ovens have a setting that lets you either see the current temperature(While preheating it shows PRE and when completed it displays the temperature you set)  or beeps when ready.