Many students have trouble understanding my steps for making a sign diagram in Lesson 1.  Here is an easier method to remember (although it is slower for most students, it is perfectly adequate for this stage of the course). 

• Once you have found the Top and Bottom Zeros and marked them on the number line, pick a number from each region and substitute it into the entire function.  The sign of your answer will be the sign of that region. 
  
• For example, if you have marked the numbers 1 and 4 on the number line, choose a number less than 1 (such as 0) to sub into the function to find the sign of that region, choose a number between 1 and 4 (such as 2) to sub into the function to find the sign of that region, and choose a number greater than 4 (such as 5) to sub into the function to find the sign of that region. 
  
• Make sure you sub the number in place of every x in the function to establish the sign of the function in that region.