I Did mine a few weeks ago..
Make sure you depressurize the system before you do anything to it.
If you have MES: disconnect the Selespeed pump (located under the sele fluid reservoir, then connect MES, select your gearbox, then click on the accumulator depressurization procedure. I'd do it twice to be safe.
If you don't have MES: Disconnect Sele pump, turn ignition to MAR and select various gears until they no longer select.. wait 30 mins to be safe, then you can work on the system.
The system runs at 55bar.. which is very high - being a Big Girls Blouse that I am, I would check, recheck and double check that there zero pressure in the system before you go anywhere near it.
Otherwise its a very easy job.
The only headache for me was getting the torx screws back in as I didn't have magnetic tipped tools.. its a very tight space to work in.. Anyway I just used a blob of blutac.
Also, you can probably get away with just replacing the o-rings on the EV0, rather than the whole valve.
Here is a table i downloaded from this site (forget who made it) that gives you all you need... Make sure they are Viton Seals though.
In my case, I just replaced the seals, all works perfectly now. It should only cost you a few pounds.
To bleed, just refill with Tutela CS and run a clutch drain procedure in MES - again if you don't have MES, I don't know what you do, so you will need to look up how to bleed the system.