Helping those who are in need of help with various Chemistry related topics...
When working on an energy level diagram, you must use the above chart. You begin with 1s, and continue on until you have the element's energy level diagram complete. Remember to follow the red arrows. This means that when you start from 1s, you continue on to 2s, 2p, 3s, 3p, 4s, 3d, 4p, and so on...
S holds 2 symbols
P holds 6 symbols
D holds 10 symbols
F holds 14 symbols
If you are wondering what a energy level diagram looks like, you can see one that has already been completed below.