Look out for the orange numbered circles, they are the steps!
(Also check out the virtual simulation game because it really helps you understand it a bit better!)
To Get The Power On: Flip the hydro switches (step 1 & 2), then turn the turbine knobs (not shown here) to 50% and switch on Substation 1.
To Get Enough Electricity: Power up the Coal and set to 50%. This gives you enough electricity! Then switch on Substation 2.
Powering Up: Now, power the towns starting with towns 1 and 2. Provide power from both substations and remeber to check the load. During peak times the grid could become unstable when switched causing outages.
Once you have the power on using steps 1 to 8 you can follow the rest of the steps. You will need to start again if you trip the substation during the process due to overloading. Once the power is on you can start booting up the other systems like wind, solar and batteries. Doing this before the power is restored could cause outages.
Remember to slow down your generation once the power is on to conserve coal and water or else your grid will run out of fuel and cause outages. If this happens you will need to switch the simulator off and on again.