I'm doing my first non-kit electronics project for computer controlled fans for my electronics closet. The person who posted the project said to use JST headers. There are two four pin connectors for two Corsair LM120 fans. There doesn't appear to be a data sheet for the fans so I looked into motherboard fan connectors and found that a Molex 0470531000 is used. I'm going to build the project on a solder breadboard (meaning one where you solder the components to a breadboard like layout in case my terminology is incorrect). Given that the pitch is 2.54mm, I'm in business. The closest JST connector I could find is 2.5mm, which I've read may not work for four pins at 2.54mm, a 120 micron difference.
The other component that will be off board and connected by a cable is the HiLetgo DHT11 Temperature Humidity Sensor Module. The data sheet for the sensor gives 2.54mm pitch. I'm assuming it's the same for the board in that it easily plugs into the connector from the Corsair fan. I've found a 3 pin header on digikey.com that looks to be correct. The page links to a connector: Molex 0022012031. It doesn't look to have pins and there is a link on the page to these pins: Molex 0008510108.
Is this how one goes about building these types of connections? I have a crimp tool and don't mind making them up. The cable has to be three or four feet long so I don't imagine I could find a stock one. Is there an easier way to do this? I've searched on the web for Molex connector kits. None looked to be the for this type. Is it typical to build connection by ordering all the individual parts or is there a more generalized approach?