1. Never EVER take a mirror selfie. 2. take a nice photo, if possible not a selfie, with good lighting that compliments your features. 3. For the writing part, share your passion. What are you into? Music, cinema, fashion, culture? Make yourself seem interesting! try something witty/clever. Don't use a deep motivational quote haha. Don't try too hard though. I'm sure it'll be great :) Gook luck
Never take a selfie in your bathroom. Put at least one picture that shows you with your friend or in a normal situation. Explain why you're there and talk about what's you're interested it. Pictures are the first thing you notice but too much men don't develop their profil page.
Something witty as their bio. Seem respectable too, I'm always dubious when guys put "always up for a laugh", makes me think they're not after anything serious. Have a photo where you're smiling. Never be too posey, it's just cringe. Have a photo with you and some friends so it looks like you're a confident, social person. That's attractive, to me at least.