If you find this a bit hard to remember, as sometimes you know the 't' should be there but isn't, review the drill several times. More then necessary.
Words withe the T: These are the words with the Final "T" is written. Sometimes it is for ease in transcribing them. Sometimes it's ease in writing.
Learning practice: Even switch it around, read one column, the next column, etc. Then read one row, next row, etc. Then read one row, skip a row, read the next row, skip a row, etc., then start over with reading the skipped rows. You may not have any difficultly, but this is an idea. After a while it will be come second nature.
"Gregg Shorthand had achieved the most extraordinary success ever attained by any system in the history of shorthand." John Robert Gregg, 1922