This section is from the book "The Science And Art Of Phrase-Making", by David Wolfe Brown. Also available from Amazon: The science and art of phrase-making.
209. For the personal pronoun I, beginning a phrase, we usually write only half the ordinary sign, striking the first half downward before certain strokes, or the second half upward before certain other strokes, according to convenience of junction. Illustrations:
I will
I shall
I do
The twostroke form for I is rarely written in phrases; so, as I becomes habitually a tick, it is properly classed with the other ticks.
210. At a hasty glance, the I tick, when made downward, would appear to be confusable with of, and when made upward, with on, as in the phrases of my and I am, written precisely alike. But in point of fact, no difficulty on the score of ambiguity has been found to arise in practice. It would seem that all danger of actual mis-reading of I for of, or of for I may be averted, if the student will,
in the few cases where it is necessary, watch carefully the context.
*Benn Pitman sign for world.
211. A uniform and unhesitating habit with reference to the upward or downward direction of the I tick will conduce to speed. To establish such a habit the learner should familiarize himself by means of the appended exercises with the appropriate tick for each of the ordinary junctions.
212. The following phrases should begin with the I tick made upward:
 
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