Determine if there is more than one correct response for any of your questions. Decide, in advance, if certain incorrect answers merit partial credit. Decide, in advance, the point-value of each question. Ideally, you should give students this information on the test itself. Post the answer key outside your office.
Students can then come by to check their performance against the key.
Distribute corrected tests in class or ask students to drop by your office to pick them up. Don't leave corrected exams out in the hall near your office. Read your students' exams with scrupulous care. Your students have invested a good many hours in preparing for, and taking, examinations. Evaluating their responses deserves your undivided attention.