I am trying to model a dome tent with four sides for an outdoor night scene but I cannot figure out the modelling approach. I have seen this question and it helps to make the basic shape, but I want to make it as real as possible with big wrinkles and stuff. I have tried sculpting and cloth sim with pinning and stuff but it doesn't look good. So if you can tell how would approach it, it would be really helpful. Thanks.
I think you should get something pretty good with sculpting, you just need to observe how the fabric behaves. Here's a quick try, I've given the object a Multiresolution modifier, when you're fine you can bake the normals, delete the Multiresolution modifier and use the normal map on the original low-res version.
Your base is great already... Maybe you should try some displacement modifier on chosen vertex groups ? Those stretches you made should be bigger, too (see your reference image, they seem to go all the way). I would try creases with a very light brush in sculpt mode, which I guess you tried already, but wider strokes with less intensity.