1. Firstly i'll start with the hair, go to the hairdressers and get it cut and use gel let them experiment with it you know spiky this that and let them decide what is the new look.
2.General hygiene- if you are someone with bad hygiene problems (you may not but if you are..) make sure your teeth are proper cleaned sort out dentistry etc. Make sure your not scruffy or have grubby nails.
3. Clothes- ok seeing as you are in your late 20's you don't want to go for clothes which are for teens or young males but the more mature male. If you want to look casual buy yourself a decent shirt and jeans and some smart shoes or trainers to help you out ask for a personal shopper and just explain you are going for something new.
I'm sorry but this is extremely hard as i have no idea how you look but try going into certian shops such as topman, gap etc. or any other shops which are great with stylish ideas for males.
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