Meaning this guide isn't finished yet and still has a lot more to come
Check back now and then to see if anything new is here

Scalables and Bricks can be found in many shapes and sizes from HUGE CUBES to tiny little curves
There useful in
E V E R Y T H I N G

Almost every build has at least A SINGLE scalable or brick, don't ask why as there useful parts

First of all, actuators, the key to functionality can be used for many things such as
Dinnar
Curves that normal bricks can't achieve(used on my 2023 Bolt Earth's hood), but overtime you may learn how to make curves out of normal bricks, don't try making curves with bricks if your new at building though)
Doors
Hoods
Trunks
Garage Doors
TRANSFORMERS
mmm actuators
And many more you can think of

You will of course need to exit editor with a 1x2 brick and move the actuator to make sure the limitations you set are the ones you prefer, otherwise wonky actuators

Sensors, the secondary key to functionality, they work great when paired with actuators as they can allow you to make AUTOMATIC OPENING NOORSDOORS
They can be used for
Autocannons(Simple)
Automatic doors(Basic)
E Y E S(Advanced)
Guided Missiles(Advanced)
Explosions on detection(Basic)
AI Turrets that can look up and down too(Advanced)
Left & Right AI Turret(Basic)
And so much more i don't know

Sensors are your friend too

When paired with sensors they can make quite the duo
You can use switches for things such as
Doors(Even a noob can make it)
Sliding Doors(Super Simple)
Blastdoors(Basic/Advanced)
Hatches(Simple)
Fans(Super Simple)
RPM Limiters[Basic]
Timers(Advanced)

Switches are helpful things that can be used in almost anything so go wild

Axles are your best friend when it comes to automobiles, they let your car drive when used with a wheel
There used for
Cars(Simple-Advanced)
Tank Tracks(Basic)
Landing Gear(Basic)
And so much more i may not know about

I recommend trying to experiment with the wheels to make some cool custom rims, not only would they look nice but also give the car some uniqueness

Want a boat? USE THEM

Float Blocks are key to a floating boat, they cannot float without them

Float Blocks can be used for
Kinda obvious

Maybe make it dinner>:)

Lights are required to see, and there used in a lot of builds, normally buildings and vehicles

Lights can be used for
Houses
Cars
Just about anything needing illumination

Perhaps it can be dinner too>:)