The fastest way is to use Color Inspector - Quick Checker. 

To be accurate it is important to 

1. Select properly Instrument 
2. Upload to ChromaChecker ICC  Profile Inspector device profiles of printers that will be used for color reproduction.
3. For non 100% opaque samples a White Backer is required
4. The user have to manage properly OBAs if exist (use proper M-conditions for measurements and ICC Profile). Please note that the M-condition mismatch may produce a huge error.