Electric Guitar

 
At each end of the guitar is a Strap Button - Highlighted in Red.
 
The ends of the Strap have a hole and a slit to aid putting on.
 
Slip the hole in the strap over the first Strap Button.
 
Slip the hole in the strap over the second Strap Button.
 
 

 Acoustic Guitar - 2 Strap Buttons

 
At the end of the acoustic guitar is a Strap Button.
 
Some Acoustic Guitars have a Strap Button at the base of the back of the neck.
 
The ends of the Strap have a hole and a slit to aid putting on.
 
Slip the hole in the strap over the first Strap Button.
 
Slip the hole in the strap over the second Strap Button.
 

 Acoustic Guitar - One Strap Button

 
At the end of the acoustic guitar is a Strap Button.
 
Slip the hole in the strap over the first Strap Button.
 
To secure the other end of the strap, you will need some strong cord.
 
Slide the cord between the neck and the strings on the tuner side of the "Top Nut". Tie to the strap with a secure knot.
 
An alternative is to use the Planet Waves Acoustic Quick Release.