The Anniversary manual classifies four applications for the abbreviation principle (paras 192-198):
1) On short words, where a sufficiently distinctive outline can be secured–usually by writing through a dipthong or strongly accented vowel: beca(me), arri(ve), cu(re), arra(nge-ment)
2) On long words, where a longhand abbreviation supplies a sufficiently distinctive outline: amt., memo., R.R., bal., deg. co-op.
3) On long words, where writing through the (first major) accented syllable sucures a sufficiently distinctive outline: un(ion), unan(imous), cap(able), delib(erate), cal(culate), abbrev(iation)
4) On long words, where writing through the consonant following the (first major) accented syllable sucures a sufficiently distinctive outline: ans(wer), aband(on), alph(abet), ord(inary)
The manual stipulates that none of these types apply when there is some ready and efficient word-building device, or when the outline is otherwise easily written.
Now print out the lists on pages 64 and 65 (10th lesson) of the *1916* manual (see Andrew’s site). On a separate page, make four lists—one for each of the “Anniversary” types. Then go through the 1916 list and write out (in shorthand) each word from page 64 into its appropriate list (testing your outline against page 65).
A good study session.
NB. Don’t bother practicing abbreviation unless your brief forms are solid (for which I recommend, along with John, flash cards).