If you struggle with fluency,
Select a short TED talk or podcast from Scientific American's "Science, Quickly" that you find interesting.
Under the TED talk video, click the "Read Transcript" button so you can copy and paste into a Microsoft Word or other document the part of the transcript text you find interesting.
Watch the TED talk at least twice, inserting "/" where the speaker makes a short pause and inserting "//" where the speaker makes a long pause. (Use pencil if you do this with a printed transcript, so you can easily fix mistakes!)
When you see / a diagram like this, / I don't want you to be afraid. I want you to be excited. I want you to be relieved. / Because simple answers may emerge. / We're discovering in nature that / simplicity often lies on the other side of complexity. So for any problem, the more you can zoom out / and embrace complexity, the better chance you have / of zooming in / on the simple details / that matter most. (Eric Berlow: "Simplifying Complexity," TED)
Listen again to how the speaker says a phrase or two and then pause the video.
Say the first phrase 5 times, following the speaker's pausing, phrase stress, intonation, etc. (If you do pause where the speaker didn't, start over at 1 again when counting your 5 times), e.g.,
What you say: "When. . . .you see. . . ."
What you think: 'Oh, no! I paused. I need to start over. . . .'
What you say: "When you see. . ., When you see. . ., When you see. . ., When you see. . ., When you see. . . ."
What you think: 'Okay, I can go to the next phrase. . . .'
Do the same thing with the second phrase 5 times.
Now say the first and second phrases together 3 times, pausing only where the speaker paused:
What you say: "When you see / a diagram like this. . . , When you see / a diagram like this. . . , When you see / a diagram like this. . . ."
Say the third phrase 5 times as above.
Now say the first, second, and third phrase together 3 times.
Continue adding one phrase at a time, listening to the video when needed a few sentences at a time, until you can say and entire paragraph fluently, pausing only where the speaker paused.
Start over with the next paragraph at step 6 above. Once you've finished practicing the second paragraph, practice both the first and second paragraphs 3 times, pausing only where the speaker paused.
Continue this process until you can give the speaker's entire speech fluently.