Hello,
your interface FastEthernet0/24 is already connected correctly as a trunk:
interface FastEthernet0/24
duplex full
speed 100
switchport trunk encapsulation dot1q
switchport mode trunk
On the FastEthernet port of the other switch, configure the same and use a crossover cable to connect both ports, that should enable the trunk link:
interface FastEthernet0/48
duplex full
speed 100
switchport trunk encapsulation dot1q
switchport mode trunk
HTH,
GP