A TV mount is a small job with real safety and finish considerations. The wall type and cable plan change the work more than the TV brand.
Describe the wall and the TV
State the wall material (drywall, plaster, brick or concrete) and the TV size and weight. Note whether there are studs, a fireplace, or an existing mount. A fixed, tilting or full-motion bracket each change the job.
Decide on height and viewing
Give the intended mounting height or describe the seating distance and eye level. If the mount is above a fireplace or in a corner, say so. The provider can confirm whether the position is practical and safe.
Plan the cables and power
Say whether you want cables hidden in the wall and whether an outlet already exists behind the TV. Running power or AV lines in a wall has code and safety rules, and may need a licensed electrician rather than a handyman.