Lately i've been using many arduino circuit simulators and 3D processing softwares. Just thought of putting them together so that everyone can make full use of the internet to their advantage.
The link to the full article is below, however if you're looking for a summary-
Tinkercad- Arduino project simulator
Everycircuit- General simulator
AppInventor 2
Thingiverse
Fritzing
If there's anything that you don't know about in the list, Check out the link below! Its a quick and informative read.
When you use your IDE, open a browser and make a tab for every net reference you may need.
Especially beginners should reference the Arduino.cc Reference Page to have quick lookup on any command they are not dead sure of every bit. Looking it up is a reinforcement learning technique that works, you'll get better.