What is Wireframing?

Wireframing 101 (English)

Wireframing 101 (Spanish)

10 Best Practices: Wireframing

Sketches (Manual Wireframing)

PENCIL: Wireframing Software

Pencil is built for the purpose of providing a free and open-source GUI prototyping tool that people can easily install and use to create mockups in popular desktop platforms.

Free and Available for Windows, OSx and LINUX

DOWNLOAD

http://pencil.evolus.vn/