Special attention is given to eliminating common handshape substitution errors, improving skills with complex initial and final consonant clusters, and synchronizing cues with spoken consonants at the syllable level.
Consonants also pose some learning hurdles.
When perception of consonant phonemes proves to be an underlying problem, the cause is often the interference of one's memory for English spelling. For some cuers a periodic mirror check is all that is really necessary. Perhaps the most effective check on cueing accuracy and synchronization is the presence of a partner who is also learning to cue and who doesn't mind monitoring your skills. One of the disadvantages of a printed manual such is this is the dependence upon written words for practice. Recall the names of relatives and friends and cue them.