For the complete Cowboy experience you can add a set of jingle bobs and they sound great as well*.
Here is how to fit a set of western spurs correctly:
First -Find the right size spur & spur strap to fit around your cowboy boot heel.
Three sizes of Spur width generally fit most riders boot heels.
1. - Spurs with Cowboy Boot Heel Width 3 1/4" - 3 1/2" fit most Men's Boots & Ladies Boots sized 8.5 & larger
2. - Spurs with Boot Width 2 1/2" Fit most Ladies & Youth- Ladies under size 8.5 & Youth Over 6 years old.
3. - Children under six will need child spurs
Second - Fit the spur to your boot heel so that, without a spur strap, the spur would most likely stay put. More often then not, you can bend the spur by hand. If you cannot; use a rubber mallet to narrow the spurs or hoof nippers to widen them.
In some cases you may need to ask your farrier to heat the spur, but be careful as this may affect the finish of the spur. And remember when you adjust your spurs you weaken them, so do this as little as possible.
Third- Attach your spur straps to spurs. Spur strap buckles typically go to the outside of your foot.
Fourth - Slip the spur over the heel your cowboy or cowgirl boot. Then buckle the leather spur strap so the strap fits snugly over the arch of your foot. You can always punch extra holes to for a tighter fit or it the straps stretch over time.
Additional Bits & Options:
* You can add "jingle bobs" to your spurs for the sound effect. However, always take time to introduce spurs to a horse that is not used to the noise because it can surprise or spook some horses.
Check Your spurs by running your fingers across not only the rowel of the spur, but also the shank and any other part that could touch your horse, to check for rough spots
And finally remember the old saying "Don't squat with your spurs on?" If you are wearing sharp spurs; take heed! You may only be squatting down to pick your horse's feet; and give your horse a good laugh and yourself a good jab.