To stop your tires from wearing unevenly you need to figure out what is causing the uneven tire wear.
Uneven tire wear can be caused by several things such as out of balanced wheel and tire, bent rim, bad shocks, bad struts or a wheel misalignment.
If your tires are wearing unevenly it would be good to get a wheel alignment which costs between $80.00 to $100.00
Uneven tire wear is usually caused by improper alignment, overinflation, underinflation or a worn out suspension.
Make sure your tires are not inflated too much or not under inflated as well.
Too much air can cause the middle of the tire to wear out unevenly and not enough air may cause the outside of the tires to wear out unevenly.
Check the suspension, shocks, wheel alignment and tire balance to see what can be causing your tires to wear unevenly.