Flash

Flash the OS to the sd card. My favorite tool for this is Balana Etcher.

Mount

After the flash is complete, mount the sd card. I will use /tmp/sdcard/ as mounting point in this example.

SSH

cd /tmp/sdcard/boot/
touch ssh

WiFi

Create this file /tmp/sdcard/boot/wpa_supplicant.conf

country=US
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1

network={
    ssid="your_real_wifi_ssid"
    psk="your_real_password"
    key_mgmt=WPA-PSK
}

Hostname

Edit /tmp/sdcard/rootfs/etc/hostname to change the hostname.

After first boot

Change your password (run this on the pi):

passwd

Add your ssh key (run this on your local machine, replace the hostname):

ssh-copy-id pi@raspberrypi