As a child he practiced calligraphy copybooks every day.
Tips
mistakes
帖 has three readings: tiě (invitation/copybook), tiē (obedient, as in 服帖), and tiè (calligraphy model, as in 碑帖). The most common modern usage is tiě, especially in 帖子 (post/message).
usage
In modern internet Chinese, 帖子 (tiězi) means a forum post or message thread. 发帖 (fātiě) means to post, 回帖 (huítiě) means to reply to a post.
Cloth radical on the left — the indexing radical, pictograph of a small hanging towel or strip of silk. Early invitation cards and calligraphy models were written on slips of silk, not paper — so 帖 lives literally in the cloth family with 帜 (banner), 帆 (sail), 幕 (curtain), 帐 (tent).
Right side 占 supplies the sound (zhān → tiě / tiē with onset shift). 占 originally pictured cracks on a divining bone interpreted by a mouth — readings forecast on a strip of bone parallel readings copied onto a strip of silk, a small semantic echo. Same phonetic anchors 贴 (stick to), 沾 (moisten).