You can make presentations by recording yourself using your desktop, laptop, mobile phone, or iPad. If you record yourself on your Mac computer, you can make use of Quicktime to record your screen or yourself in front of your computer. When you do so, make sure you have your script handy available. If you use a Windows PC you can use the app Camera.
When you use your mobile phone or iPad, put the device in a phone stand or lean it to a stack of books to have a still camera.
You may want to do a recording outdoors. If so, you need to pay attention to background noises. Be sure to sit near a light source like a window or lamp with the light shining on your face for good lightning.