The Squire is young, fashionable, and (perhaps most importantly) amorous. The reader knows that the Squire is young because he is described immediately after the famous Knight who "had his son with him, a fine young Squire. . . . twenty years of age." With this young age comes great inexperience, especially seeing that he is also described as "fresh as the month of May." In fact, the Squire doesn't have much knightly fighting under his belt except for a few topical matches to "win his lady's grace."
In regards to being fashionable, the Squire is not only dressed in the finest clothes but also mounted on his horse rather well. "He was embroidered like a meadow bright" which (at the time) was a sign of highest class. In addition, his clothes are described in further detail in that "short was his gown, the sleeves were long and wide," which again was the fashion of the day. Even the Squire's horsemanship was fashionable: "He knew the way to sit a horse and ride." In addition, he had skills fashionable for a young man at the time: jousting, dancing, singing, writing, drawing, etc.
Finally we approach the fact that the young Squire is in love with love. Within the first couple of lines we are told that he is "a lover and cadet, a lad of fire," fighting only to "win his lady's grace." Oh my. Puberty at its highest level! This amorous concept is taken further at the end of the Squire's description: "He loved so hotly that till dawn grew pale / He slept as little as a nightingale." No doubt, then, about the Squire's favorite activity during the pilgrimage then, huh? At least Chaucer interjects some laughs into his religious journey.