One rule of thumb is if "LIBERTY" is weak, it is a Small Date and if "LIBERTY" is strong, it is a Large Date. However, this is sometimes hard to determine, especially on worn specimens such as the O.P.'s coin. The other rule of thumb is that if the inside curl of the "9" in the Date points towards the center of the vertical bar (tail) of the "7" in the Date, then it is a Small Date and if the inside curl of the "9" points somewhere between the right top of the "S" Mint Mark and the bottom of the tail of the "7", then it is a Large Date. However, this is also hard to determine on the O.P.'s coin as it has damage on the "9" in the Date.
I know what you mean! I must have looked through a half a dozen rolls before I found my' first Small Date Variety and nearly went blind doing so. Once I found the link I proved in my previous post and realized what to look for, it was much easier to spot the Smal Dates.