Like 'Baltronbacon' said, you can remember it as "coming", or "comin'" except with an "a" - "camina", "camino" etc. I sometimes think of camels - the desert roaming, store-fat-in-a-hump animal - because they seem to constantly be walking to find food and water.
Because the verb 'Caminar' meaning 'to walk' is an AR verb, so the verb endings will be different to ER and IR verbs. For Example: 'Comer'= to eat. so it would be 'Él come'. 'Hablar'= to speak. 'Él habla'. 'Caminar'. 'Él camina'