Raspbian make a wifi-ethernet bridge how-to.txt

I have made a wifi-ethernet bridge on Raspbian stretch. The trick for me was following the tips from SurferTim on this rasbperrypi forum post with a similar question to yours: https://www.raspberrypi.org/forums/viewtopic.php?t=192377

Anyhow, using those guidelines that worked for me and others, here is what I would do:

#/etc/dnsmasq.conf

    interface=eth1
    dhcp-range=192.168.2.2,192.168.2.100,12h

#/etc/dhcpcd.conf

    interface eth1
    static ip_address=192.168.2.2/24

#/etc/sysctl.conf

    net.ipv4.ip_forward=1

#ip rules

    sudo iptables -t nat -A  POSTROUTING -o wlan0 -j MASQUERADE

    sudo sh -c "iptables-save > /etc/iptables.ipv4.nat"

#SurferTim says to sudo nano /etc/rc.local but I added here #/lib/dhcpcd/dhcpcd-hooks/70-ipv4-nat => use a text editor

    iptables-restore < /etc/iptables.ipv4.nat

#to use normal interface names on boot edit /boot/config.txt 

    net.ifnames=0

#Or...(achieves same as above) in /etc/udev/rules.d/70-persistent-#net.rules 

    SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", 
    ATTR{address}=="b8:ac:6f:65:31:e5", ATTR{dev_id}=="0x0", 
    ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"