I'm on conference calls all the time.

Keep the number of points you want to convey to a minimum and mentally keep yourself on the clock. 30 seconds max per point. Ask at the end if there needs to be more clarification on any of it. If not asked for clarification, don't offer it, or you'll ramble. I catch myself rambling ... :-)

Learning to be concise is hard. Even on here and on reddit, I cut out large amounts of what I write simply because I realise after spending a significant amount of time writing a reply, that a large chunk isn't directly relevant, and I'm just rambling.

It's extremely important, more than in meetings and con-calls, to be concise in your emails. Most people won't read long emails. Some will, carefully, but most skim and try to pull out the salient points. If you can be concise and make the salient points obvious, then you will be a much more effective communicator at work.

Again, keeping the number of points down to two or three, is key. Keeping the length of sentences and paragraphs short, is key. One point per paragraph.

Sacrifice less important pieces of information in order to make sure the more important information is delivered and understood.