Online resources such as Neferchichi's Tomb (see References) provide a quick and casual overview of hieroglyphics. On this site, you can match the ancient Egyptian symbols with familiar sounds in English. The "b" in baby is represented by the bottom half of a leg pointing left. The site also explains how the Egyptians grouped together pictures to form words; however, the site does not offer comprehensive language instruction, such as lessons in vocabulary and grammar. Use caution when perusing these sites. What you are learning is how to write English words by using Egyptian symbols in a quick and dirty way. This activity does not equate to learning the language of hieroglyphs.
Read about the history of hieroglyphics on history, art and archeology sites that are dedicated to ancient Egypt. The International World History Project provides a more comprehensive explanation about the Egyptian hieroglyphic system, its general characteristics and form. For example, it describes the two groups of Egyptian glyphs, phonograms and ideograms. While phonograms represent sounds, ideograms represent ideas. The ancient Egyptians typically used a combination of both groups, placing a phonogram before an ideogram to signal the reader on the context or meaning of the symbols. Again, this kind of research only provides a high level overview of hieroglyphics.
Take undergraduate courses or major in Egyptology to learn hieroglyphics. According to Princeton Review's "Guide to College Majors," a sample curriculum would include introductory courses in Coptic, Demotic and Late Egyptian. Study Egyptian Art and Architecture, Literature, Religion, Magic, History, Archeology and a selection of Middle Egyptian Hieroglyphic texts. Acquire fluency in at least one of the following four languages: Latin, Greek, German or French. A second language will enable you to read scholarly texts. Very few undergraduate colleges offer a major in Egyptology. In the U.S., training in Egyptology occurs at the graduate level; however, you can major in Near Eastern Studies.
Enroll in a graduate program in Egyptology. According to The Fitzwilliam Museum, the best programs in the U.S. are offered by the University of Chicago, Yale University, University of Pennsylvania, New York University and the University of California, Berkeley and Los Angeles. Investigate Egyptology programs in British and European universities. For example, the Griffith Institute at Oxford University specializes in Egyptology and Ancient Near Eastern Studies. The Institute boasts the largest specialized Egyptological archive worldwide. This archive includes notebooks, sketches, watercolors, blueprints of Egyptian monuments and more.