I trim on a schedule & as needed in between because split ends don't rectify themselves, they continue to split up the shaft until cut off; I learned this the hard way. I thought cutting less often would help me retain more length & by the time I'd realized how much damage I'd done it was a wrap.
I use the LCO method to moisturize. I sleep with a stain scarf and bonnet. I rarely ever sleep with loose hair; bunning or plaiting at bedtime allows the product I apply time to be absorbed as my hair dries.
I deep condition/pre-poo everytime I wash with shampoo without exception. I use sulfate shampoo & a non-sulfate clarifying shampoo; both require that I dc/pre-poo to keep my hair balanced.
I utilize hardcore protein treatments as needed & light protein in between. I have fine hair that accepts moisture more readily when it has the right amount of protein.
I detangle with light oil using my fingers first, then I follow up with a comb & a small amount of conditioner to complete the process.
I blow dry my hair on a low/medium setting after washing. I don't know why this helps as opposed to hurts honestly, but blow drying keeps my hair stretched, detangled, allows moisture to be held better, helps prevent tangles & ssks. My air dried hair is a rough, tangled mess no mater how I set it to stretch it.
If I think of anything else I'll come back & add, but all of the above has helped me to keep my hair/ends constantly moisturized && beat a series of setbacks. Also, what are you using to seal? Some oils/products are popular for others, but do not work well with my hair (olive oil/coconut oil/Shea butter). Maybe you need to trim & switch up products a bit.