To VLAN or not to VLAN

Hi need some advise I have two LAN networks (192.168.4 & 192.168.1 range) that I want to add a Wireless network to for guest and staff to use the internet on their private devices but obviously don’t want them to touch the networks so it will run on its own subnet (10.0.0. range) problem is I have a DHCP on the 192.168.4 range and also need to have an active DHCP on the wireless range (10.0.0.) so I’m thinking the best to do this is to setup VLAN to separate the networks and run DHCP on the CR200i I do not have any VLAN on my switches I have read a lot about VLAN’s and I think I understand them but it doesn’t work I think I’m missing something. Here is a setup of what I got how will I need to set it up? Or how would you setup with this equipment?
Any suggestions is highly appreciated.