Say for example you have 100mg of DPT HCl that you want to convert to DPT freebase. In my opinion, the best method requires only NaOH (household lye) and distilled water in a glass vial with a glass stir rod or a plastic straw or other plastic/glass stirring utensil.
The atomic mass of DPT freebase is 244. The atomic mass of NaOH is 40. That means for every 100mg of DPT, you want around 17mg of NaOH dissolved into the distilled water. It's probably okay to round this ratio of NaOH to DPT even further from ~1/6th to 1/5th.
Once you dissolve the NaOH in the distilled water, pouring any DPT into the solution will lead to the rapid formation of DPT freebase while the water becomes saline. I got waxy orange crystals reminiscent of DMT when I've done this, but you may get an oil. Either way, it's not soluble in water so it floats to the top or sinks to the bottom. If you get crystals you can touch them with the stirring utensil and they should stick to it and you can pull them out of the vial and wipe them off onto herb carrier or straight to your freebase pipe. If you get oil, you're on your own for as how to get it out of the water without losing any.