"Start with" is a commonly used phrase in English, but sometimes, it's necessary to use synonyms to avoid repetitive writing. Here are some synonyms for start with: commence with, initiate with, begin with, launch with, kick off with, open with. Each of these synonyms has slightly different connotations, so it's important to choose the right one depending on the context and the tone of the writing. For example, "commence" may be a better fit for formal writing, while "kick off" may be more appropriate for informal or conversational writing. Choosing the right synonym can help make your writing more engaging and varied.