How to install wall lights and its electrical wiring with switch?

I need to know about Installing new wall light step by step

from dragging wall and ceiling. to finish all ceiling and wall back to its original condition.

Before you start, buy and read Home Depots book on home wiring. It’s pretty basic and easy to understand.electricians

Things you’ll need:
3/0 cut-in or old work box for each fixture (3-oh cut in)
cut in switch box (single gang for one switch, double gang for 2, etc)
14/2 romex (12/2 if you tie in to a 20 amp circuit)
some romex staples
a junction box with cover
Switch cover plate
your fixtures

all this can be found at Home Depot or similar

Locate a constant power source. Try to avoid circuits with motors such as fridge, microwave, a/c, etc. These will dim the lights every time they turn on. Turn off the breaker. Be doubly sure that the power is off in the wire you are about to cut. You can get a little sensor that will light when next to a hot circuit.

Use the 3/0 box to trace an opening where you want your light. Use a keyhole saw to cut the opening. You may have to trim it a little to get the 3/0 box in the hole. DON’T PUT IT IN YET!!

Repeat with the switch box where you want the switch.

Now go to the attic. Locate the top of the wall above your light. Drill a 3/8″ hole there. Repeat in the wall above your switch. Run a 14/2 into the 3/8 hole and out of your light hole. Run the other end down the wall to your switch. Mark it at the switch as “switch leg.”

Now go to your constant power source. Check again to be sure it is off. Cut the wire and run both ends into the junction box. Run a new 14/2 from the junction box to your new switch box. Use wire nuts to tie all the blacks together. Repeat with the whites and bare grounds. Put on the cover of the junction box.

Use Romex staples to secure your romex to rafters. Be sure to staple within 6 inches of the box.

Now you get to go downstairs. Pull all the romex out of their respective holes. At the light, pull the romex thru the opening in the 3/0 box as you insert the box into the hole. Use a drill to tighten the screws that are attached to the wings on the box. You’ll need about 6-8″ of romex at the box.

Do the same at the switch box being sure to pull both your power and switch leg romex into the box.electrical connections

Strip the sheathing off the Romex so that 1/4″ remains in the box. Cut the wires inside to 6″. You can have a bit more but not less. Strip the ends of the insulated wires. Use wire nuts to tie the white wires together. Tie the bare grounds together along with an additionial piece of bare that is about 6″ long to form a little pigtail. Make small hooks in the blacks and the bare wires. Connect one of the blacks to one of the gold screws on the switch. Doesn’t matter which one. Connect the other black to the other screw. Connect the bare pigtail to the green screw on the switch. Insert the switch into the box and tighten it until it is snug. No need to really crank it. Put on your cover plate and you are done with the switch.

Follow the instructions on your fixture to install it. Just strip the romex and individual wires like you did at the switch.