First: Make sure the televisions can receiver ATSC digital broadcast TV, if not put a converter between the Television and the antenna switch.
Now there are two (or 3) types of antenna switches.. ONE is a box of many buttons, they are grouped something like this
Main TV,, VCR, TV 2, TV 3 and in each group there will be a bunch of buttons
ANT-CABLE-SAT-VCR (missing from VCR group) and DVD are common.
There is also a POWER button.
Make sure the power button is on and then press the "ANT" button for the tv.
Type two (more common) is a wall plate, it has a 12 volt outlet, an antenna connector, a Light and a SWITCH, turn the light on.
Now, Two ways to point the antenna. Remember the antenna is 90 degrees off the arrow on the ring.
Crank up the antenna and pull down on the ring to turn it.
Using a web site like "Antenna web" (Sorry don't have the URL handy) find the best direction (most stations) and start there.. OR, alternative quarter.
Here is how to quarter.. Start with the antenna at one end of rotation, use the TV to SCAN for channels,,, Turn 1/4 turn do it again, and again and again, note the number of stations, Now pick the best direction.
Using the tv again (NOTE some VIZO for example, may lack the needed feature) find the signal strength meter and fine tune for best signal on the channel(s) you most want.
Possible upgrades and improvements.
On the standard Winegard Sensar II adding a "Wingman" gives you about 2x the signal (3db improvement)
Replacing the wall plate with a Sensar Pro (or adding one in front of your box of many buttons) makes it way easier to point, adds a signal meter if your TV lacks, and also adds more gain to the system.. Man did that make an improvement for me.
Home is where I park it!