@Gianluca Ilengo, Welcome to EasyEDA. Some quick notes about your project in no particular order. * Use wider copper tracks. Some of you tracks are carrying small signals so narrow tracks are OK but some are for power supply: mains input and low voltage DC output. These should be generously scaled in width to suit the currents they are carrying vs. the temperature rise you can tolerate. Basically make your supply tracks as wide as you can. Better still, use a Copper area for ground on one side of the board and another for supply on the other. You have minimal tracking and lots of board space so it'll be easy to make sure the copper areas give good coverage without being cut into bits by the tracks. You can find calculators for trace width for current vs. temperature rise on the web or simply make them as wide as possible but still meeting the voltage clearances (as also given in online resources). * Add the \(newly created\) HIGH\_VOLTAGE\_WARNING symbol into your schematic and this will pull the associated HIGH\_VOLTAGE\_WARNING\_WITH\_TEXT PCB footprint into your PCB\. * The decoupling capacitor C1 is to decouple the supply at the input to U1 so place it as close as possible to pins 1 and 8 of U1. Add another decoupling capacitor C2 across the supply pins of U2. * Not sure why you need to switch the low voltage of the supply on and off rather than having the switch in the mains side (no standby current!) but if you do need to do it this way, add another 10uF 6.3V cap across the switched side of the supply and ground to reduce supply bounce as the switch contacts bounce. A more elegant solution would be to use an electronic switch in the 3.3V supply using a logic level PMOSFET (or, in a simple circuit like this, a logic level PMOSFET in the ground side) driven by a switch to 3.3V and a pulldown resistor of between about 10k - 100k to ground. * Consider adding a LED + series resistor to the 3.3V output (use a low basic current low forward drop red LED as these run at about 1.8V froward drop. Some of the higher performance LEDs and blue and white LEDs neeed about 3.5V although they will glow at lower voltages).voltages).Should the RESET pin on U1 be left floating? * Should the RESET and RX (TX?) pins on U1 be left floating? * The connectivity from U1 GPIO 0 to the U2 DATA pin does not look sensible.  * Try to find supplier info for all parts so you generate a meaningful BoM: it will help with your ordering and checking. Please read: [https://easyeda\.com/andyfierman/Welcome\_to\_EasyEDA\-31e1288f882e49e582699b8eb7fe9b1f](https://easyeda.com/andyfierman/Welcome_to_EasyEDA-31e1288f882e49e582699b8eb7fe9b1f) and recommend you read: ****How to create findable Footprints and searchable Symbols.**** at [https://docs.google.com/document/d/1ZRkPPMID68mBz9j9RMIJARNSXK12PDULZXP7kiThvDg/edit?usp=sharing](https://docs.google.com/document/d/1ZRkPPMID68mBz9j9RMIJARNSXK12PDULZXP7kiThvDg/edit?usp=sharing) (or: [https://docs.google.com/document/d/e/2PACX-1vRBxS8uUSbskSIrJrNabh0A8qp0gZmWfUG7GlXX7oltY6XC9dukqS_BU-w4F-UarCNydPWOYz10VQ5V/pub](https://docs.google.com/document/d/e/2PACX-1vRBxS8uUSbskSIrJrNabh0A8qp0gZmWfUG7GlXX7oltY6XC9dukqS_BU-w4F-UarCNydPWOYz10VQ5V/pub))

The ESP8266 connections for programming aren't enough.   See [https://www.deviceplus.com/how-tos/arduino-guide/esp-wroom-02-setup-guide/](https://www.deviceplus.com/how-tos/arduino-guide/esp-wroom-02-setup-guide/) as an example