This piece was written by Fernando Sor (1778-1839) and is study no 19 from his op. 44. It is currently a grade 5 exam piece for Trinity College of Music.
The key of the piece is D major, with the last 8 bar section in the subdominant key, G major. The repeats are unclear, but most of them are generally omitted in grade exams anyhow. However, we certainly want to finish in the tonic key, D major, so after playing the piece all the way through without repeats we'll need to play the first 8 bars again.
The texture of the piece is fairly straightforward: it has a simple melody on top and a block chordal accompaniment underneath. I'd recommend that you try playing just the top line on its own a few times, as this will help you focus on playing and hearing the melody without being distracted by the fingering for the chords.
Try and get a feel for the phrases in the melody. When we read some text out loud we make short pauses to take a breath and let our listeners digest what has been said. Punctuation marks such as full stops and commas are a guide for suitable places to make these pauses.
The same applies to music: we can break the melody into logical phrases, with a short pause at the end of each phrase and an increased emphasis at the start of a new phrase. Phrase lengths can vary considerably in music, but about 2 bars is common. In classical music such as this piece it's not unusual to see regular 8 bar sections that divide into two lots of 4 bars, each with 2 bar phrases.
Notice the ornamental grace notes in bars 3, 11, 15, 27 and 31. Remember to play each ornament so that it falls directly on the main beat (not slightly before) and 'steals' some time from the main note. Use a descending ligado (a pull off) to move from the ornament to the main note.
Finally, make sure that you play the rests written in the score, e.g. in bars 1, 4, 5 and 8. It's important that we hear the silences as well as the music.
I'll be adding an MP3 recording of this piece in the near future.