To keep you starter going add 2Tbs or more of flour and a bit of warm water, every 2 days, stir well.
If you not using it for a longer time- the sourdough should be fine for two weeks if stored in the fridge.
Keep 1 Tbs each time you prepare a bread
Put at least 1 cup of sourdough in a big bowl
Add 3 cups flour (any sort)
Add 2 cups water
Add seeds (linseed, pumpkin, sunflower, kibbled rye-soak first)
Add 3 Tbs oil
Wrap in a towel and leave over night in a warm place.
Add 2 cups flour
1 tsp salt
1 Tbs sugar
Wrap in a towel and leave for another 2 hours (at least) in bread tin. Cut and surface
Bake in 200/180c oven for 1-1 ½ hours.