I'm excited for you for your imminent package, a warm welcome to you 🥰, and I'm excited to see a newcomer here! My douching skills aren't great, but I found this guide and in particular the 2 types of douching useful: https://howtocleanyourass.wordpress.com/ 😘

In addition to Chloe's comment, just a few personal notes:

• Diet makes a big difference! Keeping things consistent, eating a good amount of fiber, etc.
• Timing can be important. For me, usually 12PM-3PM or so is a good time for me. I usually don't have to do more than a quick bulb enema (if that)
• A bidet makes things a lot better, both when it comes to anal and in general.

Hey, it's great that you're persevering in your exploration ! Our two cents as a cishet couple both receiving anal :

Your fear is very natural, and should subside progressivement as you understand yourself more and more.

The rectum is not a "storage" place for poop. What this means is that, on a normal balanced diet, unless you should go to the toilet, there will be no poop in it. A knowledgeable anal receiver knows that most of the time, only a nice thorough external cleaning as well as a soapy finger inside is sufficient for a spotless hygiene during the act. It's also very normal if you don't trust this at first, and enemas are there to alleviate it :)

However, it is very important that you don't abuse enemas. Wether by douche or showerhead, they irritate the colon walls and bring perturbations to the symbiotic bacterial populations living there.

In any way, again only our opinion but it seems shared in most kink circles we frequent : you have to make peace with the fact that you may encounter a bit a poop to have fun. This isn't scat in any way (we're very not into it), but as you probably know, anal receiving is all about relaxing, which you cannot do if you're always somewhat stressed about a bit of poop, in the place where poop comes from. So empty yourself good when you go to the toilet, clean thoroughly by the means of your choosing, and go have fun while keeping some towels or wet wipes or something nearby, with the knowledge that something may happen, and that you can deal with it in case it does :)