Whatz Up With The Tab Order

Can anyone help me figure out setting tab order. I thought this problem may have been fixed in MX. I also may not know what I am talking about…anyways can someone tell me how to set the tab order. I have a form with dynamic text boxes, it works okay on like th first three then it jumps to my navigation on the left side of the form. Any general information, Tutorials, links etc… would be appreciated