Help setting up small network with FS728TLP-V2 Switch with Telstra Gateway V7610

> *  Give fix Ip to the Switch. (Same Ip  range as per the modem)
> 10.192.168.xx

   Ok with me.  I gather (from the Installation Guide) that the FS728TLP
can use DHCP to get its address (et al.) from the Gateway.  I assume
that you can reserve an IP address for it on the Gateway rather than
configuring a static address on the switch, but it should work either
way.  The important thing is not to try to use the DSL port and the WAN
port on the Gateway at the same time.  The switch is part of your LAN;
the Internet is on the WAN side.  And connecting something to the
Gateway WAN port would, I'd guess, disable the DSL modem in the Gateway.

> Do I need to create VLAN  or not?

   Need?  No.  If all you want is a larger set of LAN ports, then just
connect the switch to one of the Gateway LAN ports.  A simple unmanaged
switch could be used as well for that.

> Use Modem / router IP as gateway?

   The Gateway LAN IP address, yes, but if you use DHCP, then the switch
should get that on its own (from the Gateway's DHCP server).