Like @ndh2 has stated, train yourself to not do it. Otherwise, your spoken audio files will be fine, but your conversations in team meetings over webex or conference calls will still have it, and it would be annoying everyone else (if it's a lot) and you wouldn't know about it because no-one is going to tell you.
Also, if you start to edit the ums out, you will quickly get tired of wasting time on doing this, and would train yourself to not do it yourself. I went through this exercise after recording youtube screencasts that are 5 to 10 mins long, and wasting about 30 minutes editing out my ums and ahems.
This is good advice, but one question: why is the default assumption here that I'm the only person I ever record?
I'm pretty good at not um-ing too frequently (20 years of public speaking will do that), but I can't exactly require all my guests for podcasts or interviews, for example, first rigorously train themselves for months!
> why is the default assumption here that I'm the only person I ever record?
Because your question was in response to OPs statement regarding screenrecording, and in that, OP is talking about video and audio for recordings he/she does, not of group meetings.
> Whenever I need to document a particularly complex task or procedure, I record a 10 mins screencast and explain the process + show the steps
Also, if you start to edit the ums out, you will quickly get tired of wasting time on doing this, and would train yourself to not do it yourself. I went through this exercise after recording youtube screencasts that are 5 to 10 mins long, and wasting about 30 minutes editing out my ums and ahems.