I'm using Switchcraft ends. They come in a few different varieties like Nickel, Nickel with gold plated connectors (what's in the photo) and also colored bodies with gold plated connectors.
Here's a link to the connector
https://www.digikey.com/en/products/detail/switchcraft-inc/3502AAU/1289068
If you search Switchcraft 3502 on that site you'll see the other colors available. There are also fancier RCA ends you can buy but I really like these.
For cable, I'd recommend doing some reading and see what people are using. I used a Mogami non microphonic cable for these but if you're making some for Phono use you may want to use a lower capacitance cable.
Tools will be a soldering iron, solder, wire cutters, needle nose pliers and something to strip the wire with. It's nice to have a multimeter at hand to check for continuity and shorts before you plug them in and find you've made a mistake.
With the materials I used for the interconnects in the picture, you're looking at ~$15 each. The ends are about $8 and the cable was (I think) $5-6 a foot. Once you get the hang of it, you can put them together in just a few minutes.
Do a search here and you'll find lots of ideas on home brew interconnects. Mine are about as simple as they get but work well and with custom lengths, the back of your system will be very neat.