It depends on your objectives and concerns.
If your goal is to use only what you need with minimal devices with the least power consumption for a small network then you can likely eliminate the switch and routers from the network completely.
If your goal is separation of networks (separate 'office' & 'guest' networks, for example) then you can plug both routers into the modem and they will each operate independently (by default). They will each receive an IP address from the modem via DHCP and create their own VLANs for their connected devices and assign their own subset of IP addresses (usually in the 192.168.x/24 scope). They might both even use 192.168.0/24, but since they're creating their own VLAN this means devices connected to one router won't talk to devices on the other router. Don't use the same Wi-Fi configuration for both routers, of course. Also, disable the Wi-Fi on the modem.
If your goal is maximum security and range with the most available ports on a single shared network environment, then your best option is to plug router1 into the modem and run an ethernet cable to the uplink on router2. Make sure that you configure router2 in
AP mode which means it will disable DHCP and allow devices connected to it to talk to the devices on the other network points. You can plug your switch anywhere along either of these networks (except directly to the modem) to add network ports to the network.
You should also understand that network devices (modems, routers, and switches) are generally the low-hanging fruit for network compromise with extensive . If you're not going to maintain each device (strong unique passwords, regular firmware updates and security checks) then you should eliminate them to remove the additional risk from your network.