Go to one of her concerts or appearances and try to meet Cher by arriving early or staying late after the concert. Look at her official Web site: cher.com to find out the latest as far as appearances and concerts. You may get the chance to meet her in person and have her autograph something for you. However, respect her privacy and only go where you are permitted at the venue. Don't ask or beg for an autograph if she is not signing any.
Check out a Web site like eBay that may sell Cher autographs. Browse through the selections and choose an autograph that comes with a certificate of authenticity. You won't be able to physically look at the autograph until after you purchase it, but eBay has several stipulations in place which protect buyers from getting scammed.
Call a celebrity memorabilia store and ask if they have any Cher autographs. These stores are not found everywhere but if you live near one, check it out. Go into the store if they do so you can look at the autographs yourself to determine if you want to buy one.