We remind ourselves of this commandment every morning in the third paragraph of the Sh'ma, the most basic of Jewish blessings.
When we think of the Sh'ma, we think mostly of the iconic first line, the one we hear whenever we take the Torah out of the ark, the one we are supposed to say on our deathbeds:
Hear, O Israel, HaShem is our G-d, HaShem is One.
But that line is embedded in a series of other blessings and commandments, and the third paragraph of that series tells us, quoting Numbers 15 37-39:
The purpose of the fringe is to protect our eyes from the temptations that will lead us astray from loving G-d with all our hearts and all our souls and all our might (which is what the first paragraph after the Sh'ma tells us to do). We will see it and be reminded, just like tying a knot in your handkerchief to remind you to do something. Seeing is remembering.
How are you going to remember to avoid going astray this year?