In my experience, the more exposure you get and the more variety you have - the easier it becomes to learn.
1) Use apps (Duolingo is my preference)
2) Read grammar books to learn and understand the underlying structures.
3) Read children's books when you have a big enough vocabulary from (1) and then advance to older books as you expand your experience.
4) Listen to media (Netflix, audio books, tv, radio etc). there should be a lot around you in Costa Rica.
5) Practice - use it as must as you can in every day interactions with actual speakers. If speaking with people in person is scary at first there are a number of services online you can find to match you up with a tutor/practice partner.
Related to reading children's books - It can be pretty rewarding and educational to actually speak to children.
I moved to Finland two years ago, and I've found my level of language is good enough to communicate with 3-4 year olds. After that they know more words than I do, but still we usually make ourselves understood.
The best thing I've found for my learning is time though, I'm definitely better at hearing the difference between "o" and "ö" now I've lived here for a long time, and heard them spoken. Listening to Finnish (metal!) radio has also helped me out even though most of the vocabulary is unknown to me, just having people speak at "full speed" and hearing it is useful.
1) Use apps (Duolingo is my preference)
2) Read grammar books to learn and understand the underlying structures.
3) Read children's books when you have a big enough vocabulary from (1) and then advance to older books as you expand your experience.
4) Listen to media (Netflix, audio books, tv, radio etc). there should be a lot around you in Costa Rica.
5) Practice - use it as must as you can in every day interactions with actual speakers. If speaking with people in person is scary at first there are a number of services online you can find to match you up with a tutor/practice partner.