President Obama’s directive to improve federal hiring processes instructs managers to increase their input into the selection of new hires. One way for managers to do so is by improving their ability to interview job applicants. Some tips: Prepare. In order to design relevant questions that will reveal a job applicant’s strengths, you must understand your job opening, the applicant’s credentials and your selection criteria. So don’t recycle old, outdated job descriptions for your opening. Instead, take a fresh look at the opening by analyzing the tasks it will require, the credentials needed to fulfill those tasks, how you want…