Hi, It's the first time I ever made an PCB design and I don't have alot of knowledge about electrical things, but I did try my best to make a PCB out of scraps from the internet. **Due to legal reasons I can't make the project public, so it would be amazing if someone would be willing to help in the private project.** The goal of my PCB: Controlling some optocouplers via an ESP32 and controlling an MDB-module. (this is the short version haha) So, starting with the MDB module, I used the schematic of Shadowlamer (found here [https://easyeda.com/shadowlamer/USB-MDB-converter](https://easyeda.com/shadowlamer/USB-MDB-converter) ) And like just copied the components onto my schematic. I have no idea how to connect this to the ESP32, but I just used pins I could find... The ESP32 (which has WIFI) is acctually 'overkill', since I don't need/want the wifi on it. So I found a small schematic on the internet with an ethernet module and just tired to connect it the best way I could (No idea if it would even work tho). Then, we have the USB controller. This would be to program the ESP (also, no idea if this is connected correctly) The most important thing would be the BUCK converter. So there is a power supply from the 6-pin connector, which is 34? volts. (it's more than 24 and less than 48 lol). But the ESP32 doesn't work on that voltage, nor do the optocuplers do. So I kinda need a BUCK converter to lower the voltage. I found one, but no clue if the BUCK converter would even work. The schematic for the optocouplers does work and does not require inspection, tho it could be cool to know if there is any improvement possible!) So that would be the electrical part.... Then there is the PCB part. It should be a 2-layer pcb (if there are more layers needed, that would be possible tho) and as compact as possble. If passive cooling (for the BUCK converter) isn't an option, then we could add a fan to it, but it's not really what we would like to add... <br> <br> Since I've never made such PCB design and my knowledge is very little, it would be amazing to have some input about this! (Like what could be better or changed). Thank you so much in advance to read this and maybe help me out! Robin