Learn Croatian: Poradit ću na svojoj prezentaciji. - I will work a little on my presentation.

It gives the verb an attenuative aspect, meaning the action is performed to a small degree or for a short time. Instead of just working on it, poraditi means to work on it a little bit or to put some extra effort into it. This makes the statement sound softer and less demanding.

Why is the final -i missing from the infinitive in poradit ću?

In the Croatian future tense, when an infinitive ending in -ti comes immediately before the enclitic auxiliary verb (ću, ćeš, će, etc.), the final -i is always dropped. If the word order were reversed, it would keep the full infinitive form: ja ću poraditi.

Why does the sentence use svojoj instead of mojoj for my presentation?

Svoj is the reflexive possessive pronoun, used whenever the object belongs to the subject of the sentence. Since the subject is I and the presentation is mine, svojoj is the most natural and grammatically correct choice, even though you will sometimes hear native speakers use mojoj in very informal speech.

What case is svojoj prezentaciji in, and what triggers it?

It is in the locative case, triggered by the preposition na. While na can take the accusative case to show physical motion toward a destination, here it indicates the metaphorical location where the effort is being applied, which requires the locative.