If I ask, what do you love the most about The Sims? Most people will say it's the building part, if not for its interesting life simulation concept. I was never really into building lots for my Sims, up until The Sims 3 I was mostly satisfied with any pre-existing lots. Sometimes I would try to build my own, of course, but looking back they were cringey and ugly as hell.
But then The Sims 4 came along and makes the building part more interesting! It's such a letdown that Create-a-Style is no longer in the game, but the new game system kinda makes up for it. So now, building lots is also my favorite part. If you can't spare 6 hours to create a perfect lot for your sims, you can simply download some beautiful lots from the official gallery or any third-party resources out in the net.
I'm not a great builder per se, but seeing all the speed build videos and all of those hours spent on building my own houses, I can give you some tips to be better at building houses in The Sims 4.
Start with themed lots
Are you going to make a minimalist house? A vintage victorian house, perhaps? Or a homey lodge? Before building, decide on one theme. One room is futuristic, the next one is a horror themed? Of you course you can always go with more than one and I don't forbid you to do so, but it's simpler to start with just one before moving on to fusion themes.
Use more than one pattern or color on a single room.
I used to only use one pattern of wall or floorings per room. But if you do it right, you can find a beautiful combination that your room looks like a real room instead of a boring block of colors.
Play with size
Yes, you can resize objects in The Sims 4. And sometimes objects are better in different size. Take paintings for example. When you enlarge it, it can fill up the room more efficiently and create a statement, rather than clumping up a group of small disorderly paintings together on a single wall (not that I'm against it though, just an example). Other things that can effectively resized for the aesthetic purpose are toy cars that act as a real car in the front of your house, rugs, rocks. Note that even after you make it bigger the placement size will stay the same, so you don't have to worry if it would block things around it.
Use Move Objects cheat
Yes, don't be afraid to use this cheat! In fact, if you want your lots to look realistic and has a lived-in feel, use "bb.moveobjects" on when placing clutters. That way, you can place anything anywhere.
Mind the flow!
Before calling it final, ask yourself: is this suitable for my Sims? Can they live or do activities here? If it's too cluttered, too narrow, too wide, etc. you might wanna adjust it so the flow of your game will be much simpler. I mean, I think I don't want my Sims to take 1 hour only to walk from their room to the front door. Be ambitious, but always remember to keep it realistic! If you checked the list, then good. That means you're ready for the next step which means..
Playtest your lots
Yes, do this before uploading your creation to the gallery. No matter how beautiful or unique your lot is, eventually it would be used with Sims in it. So make sure they're able to navigate or interact with objects properly. Just place any household there or travel there and turn off all the cheats. If your Sims can perform their activities smoothly, then you're clear to go!
Browse for inspiration
Watch building videos, inspect other Simmer's creations, look for room or lots inspiration that is possible to implement in the game. Only then your aesthetic and building sense will improve over time.
And good news: the terrain tools are making a comeback in the latest Sims 4 patch! Not sure why it's not there in from the beginning, but it definitely will step up your house building game. Now you can create multi-tiered properties and more thematic houses (vampire manor up on the hill, anyone?).
Okay, that's all from me! Hope this helps. Maybe someday I will upload some screenshots of my house creations here. Until then, sayonara~