[header] How to chalk a baseball field [title] Use a line chalker. [step] Line chalkers are small devices used to apply chalk to baseball fields. There are many varieties of line chalkers available, and specific directions for use vary with the product you purchase. 
Generally, though, you can just fill the device with marking chalk, then set it to your preferred width and wheel it across the baseball field. [substeps] Line chalkers can often be set to make either a two-inch (five cm) or four-inch (10 cm) line.