You can choose the path of the eternal suffering and try to play retal right from the start, or…
You can follow this guide and farm yourself the Perdition rare set around level 40 and follow this guide (which would require you farming the Mythical version of the set or a blueprint). Then farm the Sentinel of the Three set or a blueprint.
You can craft a bunch of Faceguards/Judgements of the Three and convert the worst of them to an item of the same set. Costs a bit of iron and some rare materials, but this might be faster than farming for the full set.
I’ve farmed Perdition in 1 hour, it’s quite a common Epic drop to be honest. I didn’t bother farming the Empowered version because the build felt quite strong up until level 94, at which point I switched to the Sentinel set.
The budget build is pretty strong in terms of damage and there are some good MIs that support acid retal. 1 death happened to get myself to lvl2 in crucible, 1 was not paying attention to resistances and the last one was to the Pit in act 2 Ultimate. Got bonked with phys damage, so I recommend avoiding it if you don’t have the Empowered version of the set.