For me it's ruthless minimalism, really. I only do things that make my life easier.
So, I don't watch tele, unless I am ill and enforcing some rest on myself. I don't invest time in my family of origin beyond duty phone calls and birthday cards. I don't participate in conversations that don't have a purpose. I frequently excuse myself from events or relationships that don't work for me or make me happy. I do not maintain relationships or habits that drain my energy. Etc etc. This leaves a lot of time and headspace for the things that matter to me.
I exclusively wear dresses and jumpsuits in bright colours. I have silk scarves and fun costume jewelry to dress them up. Separates, jeans, etc are a faff and never comfortable- my arse is too big, waist too short and my legs too long, and I bloat too much during PMT - much rather wear traditional shapes that accommodate my body tbh, and require much less styling (e.g. does this blouse go with this skirt- cannot be arsed!! A dress is much easier). Casual/lounge wear is matching gym sets or yoga wear, sized larger so that they are comfortable and supportive rather than constricted. I wear these around the house so that quick yoga breaks are easier - the more I do, the more serene I am really.
On that topic, My leisure time is meditation/yoga/high intensity cardio, sex, or entertaining friends. That's basically it. I only do things that I want to do and that make me feel happy.
I have toiletries permanently packed for travel, and I have a capsule travel wardrobe - 5 of my dresses that dont wrinkle, fav denim jacket, a men's Oxford cloth shirt for layering or as a sun cover, fav sandals, couple of silk scarves and a sun hat. Red lipstick and sunglasses, throw in a cozzie or coldweather outfit as needed - done.
I have a partner who actually does things and can figure stuff out without loads of instructions - this is vital tbh, unless you're a sahm. I work ft. Dp does dishwasher, kitchen cleaning, car things, lawn mowing, food shop, washing - and does them all well. My exh was simply unable to contribute in this way and it definitely made for a miserable, disorganized family life.
Whiteboard in kitchen as central family calendar. Works wonders.
"Present cupboard" - spirit away the toys and tat that get less attention at birthdays and Xmas, keep the nicer gift bags and tissue paper, make up generic gift bags and keep them at the back of a closet, ready to go as needed.
Sit down rarely. Clean one thing every day. Declutter something every week.
For entertaining, use a caterer if you can afford it, or learn to make attractive grazing platters, YouTube is your friend. Buy any flowers on offer at the supermarket - use Youtube to teach yourself how to arrange them simply and attractively. Dont be a perfectionist - give it a shot and be good humored about it. The effort will show even if it isn't top notch! Keep it simple and focus on making your guests feel special, rather than on getting it perfect.
Beyond that, it helps to have straight, fine hair and lots of it, as a pp mentions. I'm also tall and on the slimmer side which helps with clothing looking nice. I stand up very straight and make a lot of smiley, encouraging eye contact. That covers a multitude of sins.
Generally speaking I was trained to just get on with it, really. Assess each day with the resources you have, do your best, go to bed feeling you've accomplished some things however small, and start over in the morning. When you're tired, rest. Keep it simple and focus on what's important to you.