What is a good way to save weight on gear? Here's what I take on a 1-5 day trip

>water 2x1,5kg + chlorine tabs or squeeze type filer
>food 0.75 kg per day

>bivy tent, 1.5 kg
>sleeping bag either -20 degC 2.1kg (winter) or 0 degC 1.4kg (summer)
>lightweight aluminium-coated pad, 0.2kg-ish
>small towel 0.5kg-ish
>underwear and socks each 1 pair per 2 days, 0.2kg per day-ish
>clean shirt 0.2 kg
>jacket 1kg unless I'm wearing it
>compass, small knife, small emergency kit total 0.5kg

I want to add that I never take any cooking equipment. I never bring food that needs to be heated because it's quicker and saves a bit of gear.

I know the underwear/socks are comfort, but I like them for the weight, same as the shirt. What I might still save on is get one of those lightweight towels, and I have cheap heavy sleeping bags. anything else? I've looked into hammock camping but it's not for me.

Looking at my list