ESP32 WROOM32 - Entering Boot Loader

Hi,

I am an ESP32 WROOM32 board - NodeMCU32. The board comes with a tiny IDO button which needs to be pressed to upload new code.

This article and other sources indicate that to achieve the same with an external button, I need to ground GPIO0 on boot.

I've tried that by connecting GPIO to a switch that connects to ground when pressed. However, this seems to have no effect. Also tried pulling down via a 10k resistor, also with no effect.

Any ideas what I am doing wrong?

Is there any other way to get the board into boot mode from Arduino IDE?