HCH3CO2 is acetic acid, which is a weak acid. Weak acids are weak electrolytes since they don't dissociate 100% in water. Therefore, you can't break it up into ions when writing an ionic equation.
It helps to know which acids and bases are "strong". For your course level, there are not very many. There are at least six strong acids: HCl, HBr, Hi, H2SO4, HNO3, and HClO4. All group IA and some group IIA metal hydroxides are strong bases (the group IIA metal hydroxide case depends on solubility). By default, the other acids and bases you will encounter are considered "weak" in aqueous solution.