Flowering Nutrient start set-up

Anyone out there have a solid procedure for transitioning from 20/4 to 12/12? When to stop using veg nutes and start using bloom nutes....there's so many different methods that I've heard of, but would like some input before the final drive into finishing up my first grow

i personally feed veg nutes the day before flowering for when they stretch and then i water the 2nd day with half strength flower nutes and water normal and then feed regular strength.

Experiment and find which way you like.

By that do you mean you use the veg nutes from when you put the seed in the larger pot, up until the day for flowering. The first day of flowering you use half strength nutes, then the second day you use full strength till the end? And what about things like Big Bud, or Bud Candy?

Veg nutes all the way, up to and including the first two weeks of flower. She doubles in size in the first 2 weeks and needs to get extra N to fuel it. There's not much point giving flowering nutes to a plant that isn't flowering just yet.
After 2 weeks stretching, just change to flower nutes...