Normally and if if its the more serious down in the muddy dirty stuff, it is jeans and a few old t-shirts.
Normally get a few pairs of cheap supermarket jeans and t-shirts each Christmas for the year ahead just for that purpose.
In summer it is shorts and use a home made old jeans/t-shirt strung over wood to rest knees on, so can wash it. Saves those plastic kneelers ending up in landfill and never found them that nice to kneel on. Mine store nicely and hang in the comer of the greenhouse too.
If when it gets a little chilly here, an old jumper too and for those rainy times an old fleece with hood, that can be easily washed.
A baseball cap at all times, not just to keep the sun off but a good head hitting 'close' protection.
Shoes are slip on canvas ones, last for years and clean nicely in washing machine on sports shoes wash.
Have a pair at back door, a pair at front door and a pair in greenhouse for those muddy days to swap over with the back door pair, so do not tread near back door the dirtier ones.
Never wear gloves, except when its pulling up the stingers or dealing with the prickly holly or gooseberries during pruning.
Always have a spare old tea towel to hand for semi-wiping hands, especially if getting in deep and muddy. Have had a few on the go for years and washed hundreds of times.
An essential indoors used to be Swarfega, but that's long gone, so its a handwash and a quick nail brush rub.
Never use pockets for carrying, just have an old plastic sweet tub and lid for transporting the tools around the garden with me, like pruners, seed labels, seeds, scissors, string and towels for that planned time. Also nice that I can place the bigger tools like trowels and dibbers etc on top of the lid so do not lose, while moving around the plot.
Have the tablet sat in the greenhouse or under the patio umbrella for listening/watching while working and connected bluetooth to over ear headphones. They fit nicely under the hood if it rains.