My water intake is pretty high, but it does vary seasonally - in summer, I’ll go through 5L easily. I think that most people could stand to increase their water intake, and reports of hyperhydration are overstated - it’s mostly a paediatric problem.

• Learn to just drink a whole cup at once. Then do that on a schedule. Every hour through the working day gets you to the 2L per day generic recommendation. Then add a couple glasses at and after dinner.
• I don’t want to recommend bottled water because it’s environmentally reprehensible, but find a way to make water taste neutral. Part of that, though, is just getting used to it.
• building on that taste thing - it’s probably better for the long term to get used to it than to always add flavor.
• Find out if you like it better warm or cold. A lot of people insist on cold water, but I don’t like cold water. It takes too long to drink without a brain freeze effect, unless I want something specifically to cool me down, which is infrequent.