please help to design network

Like Chojin I send u to this suggestion
192.168.1.0 /26 (192.168.1.0 - 192.168.1.63) (59 hosts)
192.168.1.64 /26 (192.168.1.64 - 192.168.1.127) (54 hosts)
192.168.1.128 /27 (192.168.1.128 - 192.168.1.159) (17 hosts)
192.168.1.160 /28 (192.168.1.160 - 192.168.1.175) (8 hosts)

how evry pc located in ur office ? u need 1 standard Cisco router & 8 peaces 24-Port Switch. u can use all Cisco's product.
so, enjoy it