Get some distilled water and thoroughly wash some activated carbon. It doesn't take much but it is important that you clean it to keep it from ending up in the final product. Just add it to your naptha and disolved dmt. Stir it a bit and filter out the carbon. I would like to stress that dmt is just naturally hard on the lungs when vaporized so the best thing you can do is do your best to keep the lye out of your naptha. Also, if you are doing a naptha extraction and a freeze precipitation the additional steps of recrystalization and cleanup really aren't necessary and won't change the experience. They are fun, though and seeing those clear clusters of crystals grow is a treat. You will typically loose a little dmt to your filter when cleaning with carbon.
Again, I gotta say, the blastoff through vaporization is amazing and it's great to join the club but using this stuff orally with rue is, in my mind, THE perfect psychedelic. So beautiful, soo pleasureable, sex is amazing on it. Still, it's insightful and creative. It can be incredibly intense. It does take quite a bit more for proper effect though. Additionally, you can redose the dmt without more rue for a 3 or 4 hours after taking the rue. The duration is about 5-7 hours which is perfect imho. I believe it's the really pure effect that the ayahuasqueros seek with their plant brews but far more reliable and much kinder to the body.
I have noticed that it can be fickle at times. I usually dose about 5 grams of thoroughly ground syrian rue seeds (available in middle easter grocery stores as esphand/espand for much cheaper than online) and follow with 100+ mg dmt about twenty minutes later. I prefer to have a little food in me when I start and will likely eat another small snack in about an hour or hour and fifteen minutes. I have heard some speculate that , IIRC, it is possible for the dmt to end up in the gall bladder and that a bit of food with some fat in it will cause it to go back into the digestive system. That can lead to a strange effect of one thinking that the trip isn't going to happen or is just really light and then having a bit of food and wham about 20 minutes later the gorgeousnous descends. I mention that so you aren't tempted to go driving off thinking it's a dud. Been there , done that!
I'm not the religious type but this drug does really open one up to the possibilities. The experience is just so pleasurable/joyful/special. It can be overwhelming though and I've been tripping on dmt and then just wanted to go higher and higher so ate more and more and then it gets a bit unnerving. It seems that when I get to that level I tend to think that that space is my true reality and this one just the temporary state. Be careful and keep it a special experience. It's tempting to use frequently but I think that is a mistake. Enjoy.
just wanted to add that crystal size can be greatly influenced by the speed of cooling. The slower the cooling the bigger the crystals.