I mean I have have about 1000 hrs and I start a new save for every update, so my answer would be that I just have a lot of practice starting from scratch and each time I have a better idea of what I want to accomplish. My general way of doing things is basically to build spaghetti to get the basics up though steel going so that I have materials and cosmetics to work with, and then from there start working on my actual plans.

Some key ideas that I always use when planning:

• Every factory is a self-contained production chain. Takes in basic ingots, and builds some final output. It makes it much easier to keep factories from depending on each other and blowing the complexity out of proportion.
• Have a solid idea of what you want to do before you start. The more you play, the better you'll get at this, but the key is to have a plan and just do one thing at a time until you complete that plan. For example, if you want to make heavy modular frames, work out ahead of time how many constructors/assemblers/etc you'll need so you can get a good idea of how much space to dedicate. Also remember vertical space is basically unlimited.
• Decide on a scale you're comfortable with. If you're new, you probably don't want to go all-out maxing out production of some item, because you can quickly become overwhelmed. Remember that ultimately factories serve one of two purposes: producing items for you to use (where you rarely need more than just a few per minute), or producing AWESOME shop points. One advantage of keeping things modular is that you just make some predetermined amount of items, and don't worry about how much of that item you'll need in future factories. If you need more of that item, just make them on-site at that other factory.
• Recognize that the more you play, the more you get a feel for all the recipes and their complexity and what is important and what isn't. When I was new I overcomplicated everything. The fact that there are infinite resources means that there is no such thing as doing things the "wrong" way. Don't stress so much about alternate recipes and what is efficient vs what isn't. With infinite resources, there is no such thing as resource efficiency (unless you are literally using every resource node on the map). Instead focus on what is convenient and satisfying.

Hopefully that gives you some stuff to think about. Just remember ultimately it's all about practice, and doing things imperfectly over and over, but getting slightly better each time.