0- SWITCH OFF 24V on FEB/FEB2
1- Connect the USB Blaster small 10-pins connector in FPGA-PROG (J5) connector on FEB/FEB2
   TAKE CARE TO ORIENTATION : DOT on connector = RED wire on cable, i.e. RED cable side on USB side
2- OPEN QUARTUS II PROGRAMMER
3- BUTTON 'Hardware SETUP...' : select 'USB-BLASTER' in list
4- SELECT Mode : 'ACTIVE SERIAL PROGRAMMING'
5- BUTTON 'Add File...' : select the .pof file in the FPGA version directory
6- CHECK boxes : 'Program/Configure' + 'Verify' + 'BlankCheck'
7- SWITCH ON 24V on FEB
8- BUTTON 'START'

You don't have to close/open the programmer between programming session : just 
 - SWITCH OFF FEB/FEB2
 - DISCONNECT/RECONNECT CABLE (check orientation)
 - SWITCH ON FEB/FEB2
 - START Button