After understanding the basics of the simplest English consonants, there are a few more things that determine how a speaker can sound more like a native speaker or at least comprehend some of the strange sounds native speakers make, especially when speaking quickly or colloquially, for example in television comedies. You can test your knowledge of some of those features here. If you need more information beforehand, check out the post on aspiration and other special features.
Some consonants are particularly challenging for certain speakers. One of them is the affricate /dʒ/, which is often devoiced and can this way lead to misunderstandings. Here are some words containing that affricate. Listen and repeat, paying attention to your voicing (you can be sure by placing your hand on your throat to feel the vibration of the vocal fold). Pause, rewind and repeat as many times as necessary.
Another difficult, because unfamiliar, phoneme is the voiced alveolar tap /ɾ/, which is very specific to the Standard American variety of English. Actually, it sounds just like a short form of the more familiar /d/. You will come across this sound both within words and at the ends of words, but nearly always between vowel sounds. The next recording offers some good examples of words; following are sentences containing several examples of the tap. Listen a few times before trying it. Then, listen and repeat. Pause, rewind and repeat as many times as necessary.