Let's be honest, raise your hand if you would rather be behind the camera than in front. Is your hand reaching high to the sky?
BUT, there are times when, say, your hair looks good, or you are wearing a really cute top and you are seized with the thought that it would be great if someone would take a picture of you right then and there.
More often than not, that someone is YOU. If this is the case, read on.
You need to look for TWO THINGS
1) a location where you can face a light source without squinting 2) a lightly textured background that doesn't have any bright lights or reflective surfaces
If you have an indoor workspace that meets these criteria, use it! Position yourself in front of your background and face a light source.
This accomplishes a few things. You caught the catchlights in your eyes and your face will be well lit.
Either turn your head or move the camera slightly to the side. If you think it's too bright, you can adjust the brightness of your photo by tapping on it. You should see a yellow box with a sun symbol next to it. Touch this and scroll down; you should notice your image getting darker. Hold your camera phone a little higher than eye level, look at the camera view finder, and take the picture.
There are retouching apps too! I love using Perfect365. I use it to soften up my wrinkles and lighten the dark circles under my eyes.
Selfie Sticks are useful if you are looking for a body shot. The one that I have is the Spigen S520W Battery Free Wired Selfie Stick. These are great if you are taking an "ussie" (that's an actual word, by the way, and it means a selfie with more than one person).
I have an iPhone 6s, in case this matters. I am not familiar with Android devices.....