On this page you find some more neem leaf recipes.
Making your own neem leaf extract is simple. In theory, all you need is a supply of fresh neem leaves, fresh water, and something to filter your brew...
In reality, for most people the hard part will be finding those fresh neem leaves! Even bulk dried leaf or leaf powder is not easy to find.
(Occasionally I've seen it available here.)
But let's assume you either live in a tropical region where neem grows or you somehow managed to get hold of some...
If you want to make neem leaf extract to use for spraying in the garden you can soak the neem leaves for up to a week. It makes the extract more effective, but phew, it smells foul!
If you want to use it elsewhere, for example add it to your bath water for skin protection etc., then you want to strain it before it starts smelling. You can keep neem leaf extract in a dark bottle in the fridge for several days. However, depending on the use it's much safer to make it fresh.
If you don't have access to bulk leaves and don't need extract on a daily basis, then this "Neem Tub Tea" may be a feasible option for you.
To quickly make a small amount of neem leaf extract to add to the bath water just make a strong cup of tea from fresh or dried neem leaves.
Alternatively, use a bag of the already mentioned "Neem Tub Tea" and throw it straight in the bath.
To make a neem eye wash to use for itchy, red eyes, conjunctivitis etc. boil ten fresh and clean neem leaves in a liter of water for ten minutes, along with some cotton (to absorb impurities).
The same mix can be used as a gargle to treat a sore throat, or as a mouth wash to treat gum disease and prevent tooth decay.
If you can find neem tea (for drinking), you can use that. Straight neem tea is nothing other than dried neem leaves.
Boil neem leaves in water for a few minutes. Use the same amount you would use for strong cup of tea. Strain, let it cool down, and use it as an antibacterial face wash several times a day. Beneficial to treat acne and pimples.
What I said above for neem tea applies here also.