If you could offer your past self one bit of advice...

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That was not do to with romance/relationships...what would it be?

Be active ..worry less

Don't let people take advantage of you

Make each moment count.

Do the professional qualification when offered.
Ignore stepmother and encourage your dad to divorce her rather than put up with years of abuse.

Stop trying to fit in, you won't and it will stop you doing things you want to do

People who are older are just older. They are not necessarily wiser.

Take that job - he doesn't care about you. Stop waiting for him.

Stop spending money on stuff you don't need.

You're autistic. That's why everything is so hard.

Leave when I had the chance

100%

Don't drink so much in your teens / 20s, pay into a pension from the time you start working, take every opportunity to travel and see live music while you can!

Or maybe read posts thoroughly and not comment on posts that specifically say 'not to do with relationships' with relationship related advice

Have more casual sex, because you won't get any when you're older and fatter.

Don't become a nanny, you won't ever feel appreciated.

dont move back home

All of the above.

Believe in yourself.

Disengage from dicks.

Listen to people's behaviour and actions - not their words. This most of all.

Walk away from a business proposal, it's all based on lies that will take years to come out and case endless problems.

Look after your teeth !

Start pension savings early.

Don’t buy that house and move away instead.

Judge people by what they do and not what they say

Situations that don't work or have run their course are an elimination of possibilities not failures

(to paraphrase Thomas Edison)

You're not too dumb to be a vet. Be a vet.

Save as much ££ for bills etc as possible

Floss your goddamn teeth

Enjoy life more