Check the Miniart site
http://miniart-models.com (assembly guide) and this link
https://armorama.kitmaker.net/review/1425, lots of tips to be found.
They aren't all that difficult once you actually understand what the process is. The biggest challenge is figuring out what material (or how much) needs to be removed, the rest is just patience and dry fitting and gluing like you would any other styrene kit. The one thing most beginners don't realize is that once you remove the excess plastic sheet, you need to sand down the thickness of that sheet from the parts. See here for a good description of the entire process
https://archive.kitmaker.net/features/705 Some people fill the hollows with plaster or modeling clay for added rigidity and gluing tabs made from the waste material will make assembly easier. Start with one of the simpler kits and go from there. You might be pleasantly surprised at how easy it actually is. Time consuming, yes, but not terribly difficult.
Kimmo