Let's face it: kinky sex can be immeasurably complicated. Even with a large amount of conversation, it's very possible for some things to slip through the cracks. As a general rule of thumb, interests fall into certain categories; impact play, objectification, sensory deprivation, etc. Each of these categories include a number of varied activities. While - again, generally speaking - interests tend to span multiple activities within these subsets, the inverse is not always true; due to how psychological issues develop, hard limits don't always follow such correlations. And for newbies, you also can't express lack of interest in something you don't even know is "a thing."
In individual scenes this usually isn't too big of a deal as if something comes up the scene can be ended quickly without much harm. Even if we're not talking about going so far as pathological fear, there are still some things that are just such huge turnoffs that they can ruin a scene past that point. To avoid this in all circumstances - playcation or otherwise - there are BDSM Checklists/Surverys. In addition to having the ability to quickly call attention to anything that should be avoided, it forces you to think about circumstances or activities that might have not even occurred to you previously. This can be useful both for finding new scenes to try and realizing what might be out of your range of comfort, so it favors both expansion of interests and protection of boundaries.
There are a lot of forms like this on the internet but many are either poorly formatted or not customizable, so essentially you would have to print it off, fill it out by hand, scan it, and send it. This form is in PDF format, and allows you to edit as you go. Personally, I find this even more valuable so you can modify the answers should any of your interests change over time. Once completed, you can either print it off to have it on hand, or send it via email to a potential playmate. It can be a bit grueling to analyze a completed form due to the length, but if you focus on the extreme pros and cons it's apt to lead to a smoother scene.