I have written this Spanish text for the purposes of bettering my Spanish speaking and writing abilities.
How would one conjugate mejorar in this case? Would one even use mejorar in this case? I'm thinking mejorando, but that seems a bit unfit.
Usually (I'm not certain if always though) what is expressed by means of a gerund form inside a prepositional phrase in English, corresponds to the infinitive in Spanish (in prepositional phrase)...
"for the purposes of bettering" → "con el propósito de mejorar"
"for improving my Spanish" → "para mejorar mi español"