I'm not an expert by any means but I can share some of what I learned. For the Blowjob details I used Donut Smile by Meipe along with Throating G8 by iwitch. Donut smile has some extreme slider options which allows for exaggerated details, while throating has some distortion adjustment that works well with larger sizes. For the intial blowjob poses there are many packs available, so just using one that has a good start point is all that's needed.
My render settings are nothing special, I just use the photoreal setting. Most of the difference in my renders probably comes from the lighting. Similar to photography, it helps to use additional light sources along with the preexisting lighting in your space. I added some emissive surfaces to imitate functions like a key light and fill light. Basically this is done by adding a primitive that has emissive properties similar to, for example, a 80W light. Also, if your light source may be in the way in your render, you can use Oh Ghost Light by oldhiccup to add invisible light sources. I’ve added examples of how I used these in my renders, but honestly there is a wealth of material on youtube that can cover this way better than I can.
Hope this helps
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