My problem is whenever a job is assigned to me I quickly go into a panic rushing to finish the job. Because of this factor I get tense, and this results in a lot of mistakes.
Thank you for contacting Positive Personal Growth. You cause your problem by panicking unnecessarily. The next time you are asked to do something, take a big deep breath inwards, and say to yourself "I can do this" then count to ten, and concentrate on slowing down while saying the numbers.
Each time you feel the panic coming on, repeat the big breath, comment, counting to ten and the slowing down. This will get you into the habit of feeling calm, and it is this calmness that you need to enable you to work slowly and not make mistakes.