We use Screenr (www.screenr.com) to capture on-screen videos. It's a really simple system - here's a breakdown of the steps involved.
First, access Screenr by clicking the handy Screenr icon below your wordpress post (where you clicked this help icon), or navigate directly to www.screenr.com.
Click on Launch Screen Record Now button (under the intro video).
Screenr will automatically detect if you have Java installed or not. If not, Java installation is piece of cake (it may take a few minutes though). Go to Java.com and hit Free Java Download, and follow the instructions.
The Screen Recorder should now be loaded, and you'll see a resizable box appear. At this point, you'll probably want to navigate to your original blog article and position the recorder box to your heart's desire. You may also want to alter the capture size - for YouTube, 720x540 is pretty decent if you don't plan on a full screen presentation.
Make sure your microphone is on (assuming you want sound), then hit the red record button! When you're done, just click the green "Done" button.
You now have to navigate back to Screenr. If you're happy with the preview, hit Publish at the bottom. This will save the video. For Publishing, you will need to log in with either a new Screenr account, or use an existing Google account to log in.
Your video will now be published on Screenr, but you're not done yet - hit the "Publish to YouTube" on the right, where you will be prompted for your username and password.
NB: Sometimes Google will block suspicious activity - if you are sure your YouTube username & password are correct but Screenr cannot login, please login to YouTube. You may find a message appear: "Warning: Someone signed in to your account from a different location. Was it you?". Click on the "Was it you?" link and follow the instructions from there - you will of course have to say it was you, and allow the application access.
Once your video is uploaded, navigate to youtube.com/my_videos where you will probably want to edit the title of your new video by clicking the Edit button.
Happy with the video? To find the YouTube embed code navigate to the video, then hit "Share", then "Embed". You should see some HTML code in the box - copy the contents of that box then paste it into the Screenr embed code box under your new blog post.
To display the video into your post, write the shortcode "[video]" into your content whereever you please.
Don't forget to save the draft or publish your post!
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Profit!