[header] How to buy bedding [title] Choose sheets that will fit your mattress. [step] Find out which size you need to purchase by checking the tag on your mattress. Queen and king are the easiest bedding sheet sets to find in stores, while full and californian king are a bit more rare. 
Twin bedding sets are usually made for single-person beds. [substeps] Be sure to look for fitted sheets that are deep enough to fit over the mattress, and take mattress thickness into consideration.