Many questions have been asked and answered about "to + bare infinitive" vs "for + gerund" in the middle of a sentence.

However, when one wants to start explaining something, what is better?

• To do this, we will start by…
• For doing this, we will start by…

Are there even better expressions? I have not found anything concerning this situation, and I feel that the answers about the same problem but in the middle of a sentence do not apply here.