Altium Designer is one of the leading PCB designing software in the world. Even though we have free PCB designing software tools like Autodesk Eagle and EasyEDA, It is better to have experience with Altium designer. use the link below to download a free trial of the latest version of Altium.
Few advantages of the Altium designer are,
Supports Hierarchical designs.
Realtime 3D visualization of the design and can sync up with Solidworks for better design flexibility.
As a starting guide following youtube channel provides tutorials for beginners. From making a new project to Generating Gerber files for fabrication. If you check out this channel more you can learn about more advanced topics in industrial level PCB designing, which are not available in most freely given design tools.
Even though you can make custom footprints and components using the software, it is always convenient to check on the communities whether someone else has already made that component and published that component. For that install the following plugin alonog with the designer,
And also following site also provides component models for design.