@Blessed First get out the instructions and identify all the components. Lay them out and if you have to, tape a label on them!
Read through the instructions, picking up each component as it's mentioned, and identifying the ports on the back of the TV as they're mentioned.
Get a flashlight to train on the area of the TV where you're going to be working.
Do all the stuff in order.
When it doesn't work, call a friend to come and help
I didn't cry or scream or stamp my dainty little feet or shake my little pink fists even once.
When it didn't work, I tried again. When it still didn't work, I reconnected the old one, stuffed all the new parts back in the box and said "F it!"
Once you've got it working, keep the instructions!