If my goal were to take photos of myself, first I'd start with camera height relative to the height of the pose I intend to assume. Second, I'd consider the effects of distance from the camera to myself, and whether a shot looks better with a wider angle lens up closer, or with a telephoto lens further away. Third, I'd consider depth of field, how much foreground or background I want in-focus with me or nearly in-focus, and how busy those elements might be in the photograph. Fourth, I'd consider how I'm being illuminated, based on the nature of what I'm wearing, the nature of the setting that I'm in, and the ability to control light.
There are multiple ways to trigger the shutter depending on camera. Timers, wired triggers, wireless triggers, cellphone app triggers. That part is important but is relatively easy compared to figuring out how you actually want to look in the photo.
I'll use two picture of my own as an example:
Same subject, same setting. Roughly same height from the ground. The first one, shot much closer, the car looks almost cartoonish. The car already has bulbous lines, those lines are greatly exaggerated, making the nearer part of the car look much larger than the further part of the car.
The second shot is more natural looking, I'm standing further away, the distance from front to back is much reduced. This flattens out and removes some of the exaggeration.
Depending on your goal, one might be preferable versus the other. Knowing what you want to shoot and how you want to present it will impact how you set up your camera versus your subject.