If you wish to appoint skills to an applicant, it is so easy. Just go to the Talent Pool and you will notice a column named Skills. To add skills, you need to click on the plus sign that is visible at the skills column of your desired applicant.

After clicking on the plus sign, type the skills you wish to add or select the skills from the list which consist of the skills added from Settings. If you type a skill that is not on the list, then you should click on Create or press Enter.

Click on Assign skills and you will notice the skills will be appointed to the applicant.