To change the Entry Assist parameters, select the Entry Assist category
from the Session Profile dialog box.
To set any of the margins, move the cursor to the entry area and type in
a valid column number. For Model 2, 3, and 4, the valid column ranges are
1 through 80 inclusive. For Model 5 terminal, the column range is 1 through
132.
You can set the right margin as a normal margin which will either lock
the keyboard or wrap the text (if word wrap is enabled). The Alternate
right margin allows you to type over and past the right margin when word
wrap is disabled.

You can set the column tab in two ways. First, move the cursor to the Tab
Stops entry area and enter a valid column number. Then click on the Set
button to record the value.
The second way is to set columnar tabs visually. Click in the Tab Stops
entry area and simply move the dialog box from over the main 3270 or 5250
window (do not close it) and click anywhere on the 3270 or 5250 screen.
The column location will be calculated and automatically added to the Tab
Stops list box.
To clear a tab setting, select the tab stop entry and then click on the
Clear button. To remove all tab stops, click on the Clear All button.