Sourdough baking is fraught with lore and myth. I am neither an expert nor a
veteran but I am a skeptic and rarely satisfied with a 'just because' answer.
Everything I say is empirically supported by my own experience.

Think of sourdough start as wheat, water, yeast, and flavor, for that is
exactly what it is. The yeast/lactobacilli culture needs to be kept healthy,
but sourdough is really quite robust if you know how to revive it. You want
your start to be active when you use it in a recipe. To activate it, put a
little in a glass container and add flour and water with a 1:1 ratio by weight
(this is called 100% hydration in baker's terms. 1:1.5 would be 150% hydration.
1:1 by weight is approximately 1:.5 by volume). Generally you put in 2-4x as
much flour as start. You can feed it a lot more too, if you like (it would just
take a little longer to reach the same proportion of active yeast - but not
much since yeast grows exponentially). Let it sit at room temperature until
it's nice and bubbly. If you want more sour, let it sit longer. If you let it
sit too long the yeast will begin to die off and you'll have unfavorabl alcohol
byproduct (hooch), so if you want super-sour let it do its thing at a slightly
lower temperature (the lactobacilli will still grow but it will slow down the
yeast). Conversely, speeding up the process with higher temperature will give
you more yeast and less lactic acid (sour). Just keep things below 100 degrees
F, to avoid killing things. Before introducing other ingredients, take some
start and refrigerate it for the next time. A few tablespoons is sufficient.

Sourdough pancakes/waffles are fun because they taste good and require no skill
(the sourdough is just for taste, not rising power). To make bread, you need to
brush up on your algebra. Bread is really mostly flour, water, and yeast,
usually with salt, and sometimes with sweetener and other additives. To adapt a
bread recipe to sourdough, you take out the yeast and adjust the flour and
water as appropriate. Generally I use %20 of the flour weight in sourdough
start. Some use more, others use less. Experiment! If your start is at 100%
hydration, then 1/2 the weight of it is flour and the other half is water.
Reduce the flour and water to be added later appropriately. Apparenlty most
recipes call for 60% hydration dough, more or less. That's about as low as you
want to go (and makes a not-so-sticky dough, which is easy to handle), and many
like 70% or 80%. So while you've got the calculator and algebra out anyway,
experiment with total dough hydration too... Sourdough's yeast is slower than
commercial yeast, but tastes better. So your rise times will be longer. This
particular start is fairly active (or it could just be we're at a high
elevation here) and doesn't take as long to rise as some people say their
sourdough takes. Just let it rise until it's risen. (See Laurel's Kitchen Bread
Book for an excellent understanding of when dough is properly risen) If you
want more sour, deflate and rise again.

Well, that's all the scatterbrained introduction you need. The rest you can get
from the FAQs, or ask me questions. The only hard and fast rule is don't forget
to keep some start for the next time. :-)