Here are two simple dry scalp recipes, the ingredients are easily found in the supermarket. You can substitute carrier oils (olive, coconut etc.) to the ones that suit your hair best.
I usually use castor oil instead of olive oil; any carrier oil can be used. The aloe vera and the peppermint are very effective dry scalp treatments; the oil is to mitigate any drying effects that the aloe vera may have. If like me you plan to use this pre-poo overnight you can use the carrier oil. If not, you can easily leave it out.
1 tbsp olive oil
5 drops peppermint oil
1 tbsp aloe vera gel
Method: Blend the aloe vera gel in a blender until smooth, mix oils in the gel and then apply to dry hair from root to ends. Leave in hair for an hour or overnight.
This shampoo is really easy to do. Frankly, I use it as a body wash too, the essential oil is just for scent, though it has a host of benefits including relieving dry damaged skin- it is optional. The ingredients for this might take a little searching for but it is worth it and if you make large batches, you have shampoo and body wash for a while.
1/3-cup liquid Castile soap
1 tsp Shea butter
1 tsp carrier oil (castor oil was my choice)
1 tsp jasmine essential oil (very expensive but smells soooo good)
1-tablespoon vegetable glycerin (gives the shampoo lather, great moisturizer)
Method: Heat shea butter until melted, mix ingredients together and shake in bottle. Shampoo hair, any left over- use it in the shower.
Caution: jasmine oil induces labor, should not be used by pregnant women without doctors advice. It also impedes concentration because it is very relaxing on the senses.