I just started OC'ing my A7V so I should be able to give you some answers. Also I have to manual right here. First of all you can find all the settings at ASUS web site. You have to switch the JEN jumper to 1&2. It is located a few inches to the right of the 2nd to bottom PCI slot. All the other setting should also be printed right on the motherboard.
Second question: I use the dip switches myself as I asked the same quetion before and they all said they use the dip switches.
Well, actually you can use a combo setup. In my case, I set voltage and multiplier (well, only works this way), using jumpers/dips, and fsb trorough bios setup. You can do it setting to jumperfree, but still setting with dips/jumpers. It's the best adjustaments I acomplished. Due to issues with bios 1005C (at last with me) and rev 1.02 boards, everytime you boot up, the jumperfree voltage settings in bios are reseted to default, crashing your overclocked system! I don't tryed with older bios. I'm just waiting to the 1005D. :'(