Single mum for the last 15 years, worked full time. I am ORGANISED!
I have no option. If I wasn't things would go wrong. It is massively in my interests to be organised as I am completely 100% responsible for me and the DC and if things go wrong the only person who can sort it out is me.
I have a rolling list of things to do in my head. I never make written down lists, I just have it all in my head, constantly all the time.
I never put off what I can do today, because I've learnt the hard way that sometimes tomorrow is too late.
I make the internet work hard for me, so I shop online for pretty much my entire life, I book holidays online, I do all my banking online, I organise my utilities, insurance online etc etc etc. Everything that can be direct debited is etc.
Basically I am always looking to streamline and make life more efficient because that means I have time for myself.
Being tidy and making the most of storage really helps me too. It is much easier and quicker to clean rooms that aren't covered in clutter. A kitchen surface with nothing on it takes one minute to wipe down - if you have to lift up 15 things to clean under them then you are probably talking 5 minutes.
If everything has a place and you know where it will be, you can put things away easily and you never lose stuff - again precious time saved. This goes for domestic admin too. File stuff immediately and then you know where it is.
Keep on top of laundry and clean as you go a long, so that nothing ever gets overwhelming.
And my best tip of all is to get the DC to help. Start them young with 'helping' to tidy away toys at the end of the day and get them more involved as they get older. I always tell mine that if they want me to do fun stuff with them or for me to drive them to parties etc, then they have to help me, or otherwise I'll be too busy or too tired.