Define you phonetic inventory, and syllable structure.Choose your vowels and consonants. Use the IPA chart and examples at UCLA to hear and structure your chose phonemes. Listen to your chosen examples both in isolation and how you think they would be in complete words. Your phoneme table should include the IPA symbol, (optionally a romanized gloss), an example word (and translation).
Also give your syllablic structure for your language. What consonants may appear before, or after a vowel, what consonant clusters do you allow (disallow). Give examples. Are any of these related to borrowed words, morphology etc. Remeber human pronuncable languages (usually) go from (optionally) unvoiced to voiced to (optionally) unvoiced phonemes. This is often also an order restriction of asperates/fricatives, stops/nasals, glides, vowels, glides, nasals/stops, asperates/fricatives, in syllables, you don't need to support all of these, but think about what complexity you wish to have.
Identify some unusual or distinguishing aspect about your phonetic inventory.