Re "it won't save money" - well it depends. I definitely have saved a ton of money making curtains, cushion covers, bags, PJs etc - but it depends what fabric you. use and what you would pay for ready-made.
Often I see something I love but it's expensive so I make my own version, so for example I lusted after an orla kiely sling bag, cost £150-ish, I made my own very convincing one using John Lewis oilcloth, cost about £15. But of course you can get a cheap bag for £15 so if you're trying to undercut the cheapest prices, then no it won't save money.
I did my own very large curtains for my front room, and I did spend c. £100 in fabric, because I wanted it tp be quality, but it would have cost more to have them made to measure, OTOH I could have spent less in Ikea.
Fabric can be expensive, but there are lots of cheaper options, remnants, old fabric for sale on ebay, and what I often do, buy a dress or skirt or bedding on ebay because I like the fabric, and then customise it ot cut it up to make something else.
It just gives you a lot more options and freedom. I like it because I'm tall with very long arms and long waist and I can make a dress or top to fit and flatter instead of trying on 50 dresses that won't sit right - etc.