Originally Posted by OOfff

making a starter is extremely simple and often overblown. Mix equal mass water and flour. Let it sit for a day. Add double mass flour and water day 2. Repeat until you’re adding 100g or so of each every day. Then take the starter, discard all but 50g and add 100/100 to it. Repeat until about day 8. Once you have a nice ripe apple smell, you’re good to go.

so:

day1: 5g water/5g flour. Cover and set aside at room temp.
day2: 10/10
day3: 20/20
day4: 40/40
day5: 80/80 or discard all but 50 and do 100/100 if you’re getting good smell and not cheesiness.
day6-8: discard all but 50 and add 100/100

after 8 days or so, either bake and feed every day at room temp, or throw it in the fridge and do a discard/feed cycle once a week. I find that if I get a fairly mature (14-21 day) starter and starve it for a day or so, it really improves the depth of flavor development.

other tips: starter are fairly hardy. You don’t have to freak out about a missed feed cycle or if it’s not acting right straight away. Keep on feeding and cycling. It will recover unless you absolutely forget about it for 3-4 days (room temp) or weeks (fridge).

you can make cool stuff with the discarded starter, like crackers and such if you aren’t making a full loaf.