Open Settings
Tap Apps (or Application manager)
Tap the app you want to clear cache for
Tap Storage (or Storage & cache)
Tap Clear cache
Repeat for other apps if needed
To clear cache for all apps (if available):
Open Settings
Tap Storage
Tap Cached data
Tap Clear
To clear system cache (recovery mode):
Power off the device
Boot into Recovery mode (hold Power + Volume Up, or Power + Volume Down, depending on device)
Use volume keys to navigate to Wipe cache partition
Press Power to confirm
Reboot system now