I think the easiest way is to remove it completely. If it's clear that you are talking about yourself, you can cut it out and the sentence is still perfectly good. So you can say ハセベです. Another way is to use other words, like ぼく, which is often used by males. So basically you can say ぼくは/私は in your first sentence, then cut it out in the following ones (until you change the topic of course, in which case you have to state it with は). I'm not a native but hopefully you found this helpful!