The easiest way to get shinies in Sword and Shield is via Dynamax Adventures in the Crown Tundra. With the Shiny Charm, each Pokemon caught has a 1/100 chance of being shiny, and if you catch all 4 Pokemon, you essentially have a 1/25 chance every Adventure to get a Shiny Pokemon. Without the Shiny Charm, odds are 1/300, or a 1/75 chance for every Adventure.
If you don't have the DLC, Masuda Method is your best bet, with odds of 1/512 with Shiny Charm and 1/683 without. I assume you already know how to do Masuda Method as you already asked a question about it.
Of course you could always do RNG manipulation to secure yourself a guaranteed Shiny Pokemon. This is very advanced and requires outside hardware, but I just thought I should mention it.
You seem to be really wanting a Shiny Pokemon, based on your question history. Don't fret, just keep at it and you'll get your Shiny Pokemon eventually. It's important to be calm and not get too high of expectations. Good luck!
