Step 1: Download Raspberry Pi Imager

1. Visit raspberrypi.com/software.
2. Download and install Imager for your operating system.
3. Put the microSD card in the reader.

Step 2: Choose Device, OS, and Storage

1. Click Choose Device → Raspberry Pi Zero 2 W.
2. Click Choose OS.
3. Click Choose Storage and select the card.

Which OS to pick, on this board specifically:

• Raspberry Pi OS Lite (64-bit) - the right default. No desktop, so almost all of the 512 MB stays available for your project.
• Raspberry Pi OS (64-bit) with desktop - it runs, and it is slow. Worth it only if you genuinely need a GUI on the board itself.
• 32-bit - only for old software that needs it. The Zero 2 W’s processor is 64-bit.

Lite is not a compromise here. A desktop on a board with half a gigabyte of RAM spends most of that RAM on itself.

Step 3: Configure It Before Writing

Click Next → Edit Settings. On a headless board this is not a convenience, it is the only chance to configure anything - there is no keyboard attached later to fix a typo.

On General, set:

• Hostname - something you will recognise, e.g. zero2
• Username and password
• Wi-Fi SSID, password, and Wi-Fi country - mandatory on this board. With no Ethernet port, a Zero that does not join Wi-Fi is unreachable.
• Locale and keyboard layout

2.4 GHz only. The Zero 2 W’s radio does not do 5 GHz. If your router publishes both bands under one name it will usually work; a 5 GHz-only network is invisible to it.

On the Services tab, enable SSH with password authentication.

Step 4: Write, Then Boot

1. Save the settings, confirm the right card is selected - writing erases it - and click Write.
2. Eject the card and put it in the Zero.
3. Connect power to the socket marked PWR IN.
4. Wait. First boot resizes the filesystem and takes 2–4 minutes on this board - noticeably longer than a Pi 4.

The green activity LED flickering irregularly means it is working. A steady or absent LED after several minutes means the card did not boot.

Step 5: Connect Over SSH

From a terminal on your computer:

Accept the fingerprint, enter the password you set, and you have a shell. There is no desktop to miss - on Lite there was never one to begin with.

Update it before anything else:

This takes a while on a Zero. A full upgrade on a fresh image can run 10–20 minutes; it is unpacking on a single slow card, not hung.

No Wi-Fi Available? Use the USB Port as a Network Cable

The Zero’s data port can pretend to be a USB network adapter, so the board appears on your computer over the same cable that powers it. Useful on a locked-down network, or when the Wi-Fi details were wrong and you cannot get in to fix them.

Put the freshly written card back in your computer and edit two files on the boot partition - the small one Windows can see:

cmdline.txt must stay a single line. An editor that adds a trailing newline or wraps the text will stop the board booting entirely, with no error you can see. Notepad on Windows is safe; be careful with editors that "helpfully" reformat.

Then connect the cable to the port marked USB rather than PWR IN, wait a minute, and ssh to the same hostname. The board draws its power from that port too.

Living With 512 MB

This is the constraint that defines the board. Four cores, but a third of the memory of a Pi 4’s smallest variant.

• Prefer apt install over building from source - compiling large projects on this board will swap itself to a standstill.
• Install pip packages with --no-cache-dir so the wheel cache does not fill RAM.
• Run headless services, not desktops. One Python process and a couple of daemons is what this board is for.
• Heavy swapping wears the SD card. If a workload swaps constantly, it belongs on a bigger Pi.

First Task: Blink an LED

The Zero 2 W has the same 40-pin header as every other modern Pi - on the plain board it is unpopulated, so it needs headers soldered, or a solderless press-fit header.

Wire an LED:

• Pin 11 (GPIO17) → 330Ω resistor → LED long leg (anode)
• LED short leg (cathode) → Pin 9 (GND)

gpiozero is preinstalled on Raspberry Pi OS, including Lite. Save the file over SSH with nano blink.py and run it with python blink.py.

Troubleshooting

• Never appears on the network: the Wi-Fi country was not set in the Imager (the radio stays off without it), the network is 5 GHz-only, or the credentials are wrong. All three need re-writing the card.
• ssh: Could not resolve hostname: .local names need mDNS. Find the IP in your router’s client list and use that.
• Boots, then dies under load: underpowered. A laptop USB port cannot reliably run this board - use a 2.5A supply, into PWR IN.
• Nothing at all on HDMI: the socket is mini-HDMI, not micro-HDMI like the Pi 4. The adapters are not interchangeable.
• USB gadget mode does nothing: the cable is in PWR IN, or cmdline.txt got a line break. Both are silent failures.
• Everything is glacial: a desktop image on 512 MB, or a slow SD card. Reflash with Lite and a Class 10 / A1 card.

Where to Go Next

• Attach a Pi Camera with the Zero’s narrower CSI cable and build a battery-powered camera.
• Run it as an always-on sensor node posting to MQTT - it idles at about a watt.
• Read the Raspberry Pi 3/4/5 tutorial for the desktop and RealVNC path on a board with the headroom for it.
• Compare with the Pico W when the job needs no Linux at all - it will run for far longer on a battery.