Help configuring a vlan

Hello! I am in need of assistance for configuring a vlan on my network. I am using a Firewall as my network equipment and have Administrative access to it. The network is fully configured, but the configuration is incorrect. As such, I require someone experienced to help me reconfigure it correctly in order to set up the vlan. With your help, we can get the vlan configured properly so that my network runs as efficiently as possible. Thanks in advance!