Arranging and mounting military or other medals in a proper order on your uniform or on a rack requires a bit of research. Typically, each medal has its own order of precedence and you should mount them in the correct order, with the lowest-ranking one first.
Identify the medals you have. Are they military or civil? Do they have a hierarchy or a special order of precedence? You can find this information from the organisations from which you received the medals.
Purchase a medal mounting rack from your local military clothing store or online from one of many vendors. If you buy online, make sure the seller is a military-approved vendor. If your medals are non-military, you can buy a rack from any vendor.
If you are mounting the medals on your uniform, make sure your medals come with ribbons. If you do not have ribbons, buy them at a military clothing store. You can wear civilian medals without any ribbons and mount them as you like--usually, you can just clip them on if they do not come with a ribbon. However, most civilian medals also have a ribbon.
Determine the order of precedence for your medals. You can find this information in the uniform instruction regulation of your particular branch of the military. This information is typically available online.
Non-military medals may also have regulations or instructions on how to wear medals properly. Because regulations differ from one organisation to another, consult the body that presented you the medal on how to wear it. If there are no explicit regulations in this regard, feel free to mount and wear the medal as you see fit.
Mount your medals on the rack or on your uniform. Start with the lowest-ranking medal, and then work your way to the top, right to left. Make sure you comply with the relevant instructions or regulations and follow the order of precedence. To mount a medal, pin it on through the ribbon that goes with the medal. Some medals come with a mounting mechanism that doesn't have a ribbon. In this case, the back of the medal has a clip that you can use to attach the medal to the clothing.