Publication 463 explains what expenses are deductible, how to report them on your return, what records you need to prove your expenses, and how to treat any expense reimbursements you may receive.
Changes to Page 34 of the 2018 Publication 463 -- 06-MAR-2019
Other Items You May Find Useful
About Publication 15 (Circular E), Employer's Tax Guide
About Publication 225, Farmer's Tax Guide
About Publication 521, Moving Expenses
About Publication 527, Residential Rental Property (Including Rental of Vacation Homes)