Things You'll Need
Instructions
Grade and Describe Your Cards
Have your cards professionally graded either by Professional Sports Authenticator or Beckett Grading Services. There is a fee, but it immediately increases a card's value and gives buyers peace of mind.
If you don't wish to pay the fees, grade them yourself but be thorough about their condition: corners and edges, both surfaces, and picture centering.
Make a list of the cards with their grade and include all information: athlete, year, card company, and card number (located on back corner).
If possible, scan both sides into your computer or take a picture for the buyer to refer to.
Find the Book Value
Purchase a Beckett price guide from a bookstore or trading card shop. You cannot check the book value of a card online without signing up for an expensive online subscription.
Catalog the book value of all cards. If a card is not listed in the pages, it falls under the "common card" label. Do not throw these out--some people may want them to complete a set.
Make a new list of the lowest price you are willing to sell each card for with the grading information you already have.
Determine which cards are most important (highest in value) so that you can list them first.
Presentation
Purchase plastic sleeves, cases and bulk boxes from a trading card shop.
For individual card selling, place in a soft plastic sleeve.
Place the now-covered card in a hard-plastic case.
Remaining cards to be sold as a lot (50 to 200) should be placed in a cardboard box made specifically for trading cards.
Listing and Selling Cards
Create a free account on both auction websites and sports card outlet websites.
List the best cards in an auction format or at a high fixed price. While auctions are risky, they often create higher exposure and demand.
Refer to your notes and list second-tier cards for a little below their book value. Sometimes there will be a "best offer" option, which can help you achieve getting a good return even if it isn't face value.
Sell common cards individually at a low price (10 to 25 cents). These will take a while to sell but can add up over time.
If you choose not to list commons individually, auction a boxed lot at a low starting price. To increase buyer interest, throw in cards of a few star players.
Once you make a sale, the site you are using will prompt you to customize the method in which you will start receiving money.