How to translate English strings in the UI?

The main features are displayed already in Spanish, and some I could change while doing the first setup, but there is still a lot of text in English that I would like to translate. What´s the best way to do that?
I thought using Loco plugin. But I would prefer, if I am already translating, to share the translation with other Spanish Anspress users.
If translations are already available and I am missing it big time, please let me know 🙂
Thanks!