If your company insists on a constant descent then for a 3 degree glide a general rule of thumb is that you will need to lose 300ft per nm.
So at 5.5 from touchdown (or zero dme since the VOR/DME is on the approach) you need to be at 1,900ft. 6.5 would be 2,200, 7.5 2,500, 8.5 2,800ft and 9.5 3,100ft and so on.
The procedure starts at 3,000ft so therefore to keep it all nice and simple you could probably expect ATC to give you a vector no tighter than 10nm from the threshold. If you are in config 2 at this stage and speed back at something reasonable like 160-180 knots then you will be in a reasonably strong position.
Since it doesn't appear that you are approved either by your company or state to do these approaches in managed mode then once cleared to intercept the 342 inbound you can select TRK/FPA. ATC will probably clear you to descend to 3,000ft as well. Using my rough maths above you can select a -3.0 "glide" on the FCU and start down around 9.5 from the threshold (set up OEMD34L on the PROG page to monitor). At 8.5 you should be at 2,800ft as a rough check. The first published check is at 5.5nm (zero DME overhead the KFA) where you should be at 1,900ft. From then on the DME will count up and you can refer to the altitude checks above the profile at the bottom of the plate.
Finally make sure that you check through the maths and discuss how you are going to fly the approach with the other guy beside you during the brief. Give them a copy of the check heights that you worked out so that they can back you up and advise if you are high/low/"on glide" as you go down.