What are your time bottlenecks? I find that thinking is my usual bottleneck, so improving my typing speed (already good) would do approximately nothing. On the other hand, if typing is not fast and natural to you, it may well be slowing you up.

Are you trying to do more than is required? Usually, a business will want lots of good work out of you rather than less but more polished work, and adding features that aren't going to be used wastes time and money with no business return.

Are you being too hasty? Under time pressure, people frequently skimp on up-front design and planning, hoping that it'll work out anyway. It frequently doesn't.

Are you handling time properly? Development requires chunks of uninterrupted thinking time, or you'll be inefficient, and hence slow.