Being a mechanical engineer, it would be helpful to learn to speak Deutsch. Will reading newspaper headlines in German papers help, or what else should I do?
Reading will help to improve your reading skills. Reading means: Consume language that others have produced without being able to hear it. Of all the possibilities to interact with a new language, reading is the most useless way to practice speaking skills.
When you write in German (and get your writings corrected by someone who speaks German), you will be able to actively produce German text. You can't learn how to produce new sentences just by passively consuming what others wrote. (Reading helps a little, but reading alone is way to little.)
When you listen to a German speaker, you will be able to learn how German sounds. You never can learn this just by reading and writing. You have to listen to native speakers of the German language. Don't listen to Asian speakers, who learned German form other Asians, who learned it ... I've heard Asians speaking what they thought was German, and what they thought was English, but it was not understandable at all. On the Internet you can find German radio and TV stations, and on YouTube you can find German videos. Watch them, listen to them!
But listening is way too little to learn how to speak. There are phonemes in the German language that don't exist in Asian languages, but it is important to be able to produce those vowels and consonants correctly if you want to be understood. So you have to SPEAK! Try to imitate German native speakers!
Only speaking helps you to learn to speak!
The German Wikipedia (de.wikipedia.org) has a portal called "Gesprochene Wikipedia". There you will find a large selection of Wikipedia articles that you can read as the text is read to you. The articles are spoken by real people, the same way as spoken text is done with audio books.
The control to start, pause, back up, and restart the spoken article is down at the bottom of each article. Some long articles have several different speakers, so you the listener can hear different speakers and their pronunciations in one article.
By using an article's 'tape speed" control you can back up and repeat a word, phrase, or sentence (ALWAYS out loud so you can actually hear yourself) following or mimicking the pronunciations of the speaker. You will find that after you have repeated a spoken word, phrase or sentence that has been read to you several times that after ten or so of doing your own 'repeat after me's" by backing up the 'tape' you will find yourself increasingly being able to start closely matching the Wikipedia speaker's speaking speed, pronunciations, tone, and inflections.
You will be pleasantly surprised at how well you will be speaking Wikipedia-correct German by simply reading and repeating those spoken Wikipedia texts (and once again, ALWAYS, ALWAYS, out loud !!!). Remember, you do not have to stop and learn the vocabulary in a spoken article. The whole objective is to learn how to correctly speak the German language. And above all, don't try to translate what you are reading. Certainly keep a good German<-->English dictionary close at hand, and stop the tape whenever you want to 'look up' the meaning of a word that you've read/heard spoken. Keep your main priority with this method of learning as being able to speak German correctly, so you will be understood by native speakers of the language.
Because the 'tape' control is inconveniently placed at the bottom of the article, it is quite easy to generate a second copy of the de.Wikipedia, which you can then use to turn to the article you have selected in your original copy, then scroll down the page where the 'tape speed' controls are located, then use the ALT+TAB (pressing ALT first then TAB) keyboard keys to switch back and forth between your two copies, making it easier for you to control your 'tape' speed without breaking off from the point in the article that you're reading.
In computer jargon this multi-copy procedure is called "multi-tasking" -- and all contemporary computers can do it.
Actually for spoken German you need a language environment,a group learning. Reading a newspaper will help you up to some extent. But you should join any German learning institutes. Goethe institutes are best for such learning.
I find watching German films that are about things I know a lot about helps, for example I am a WWII enthusiast and watch documentaries and war movies in German so I don't have to read subtitles I can just watch and since I already know about the events taking place I can infer what they are saying. It is like reading and figuring out the meaning of a new word using context clues except you're listening instead of reading. Another thing is popular culture, if you listen to music or use websites often, make your youtube or facebook page to be in German. Making things you use daily to be in German will force you to be like "Hochladen" what does that mean? Oh! Thats right, it means upload. Also just seeing the blue text box in the top right on youtube is something you already see if you use youtube daily. Recognition is key. If I watch movies I try to watch them in my first learned language and then in German. Also repetition helps, re-watch and re-read, If math class taught us anything, it is repetition is the best way to learn! However, keep in mind that films or anything online can be Umgangssprache (slang) and may not be standard or formal.
Eine sehr gute Möglichkeit, Deutsch zu lernen, ist es, den Deutschlandfunk zu hören. Der Deutschlandfunk ist ein öffentlich-rechtlicher Radiosender (das ist so etwas wie "vom Staat finanziert, aber nicht direkt von der Regierung abhängig") mit sehr hochwertigem Programm (sehr guter Journalismus, sehr gute Aussprache). Man empfängt Deutschlandfunk heute natürlich auch übers Internet.
Das setzt natürlich eine gewisse Kenntnis voraus, insbesondere beim Wortschatz.
Wenn du noch sehr wenig Deutsch verstehst, kannst du am Freitag um 20 Uhr Deutscher Zeit dort die "Nachrichten in einfacher Sprache" anhören.
Fast alle Sendungen sind auch nachträglich im Internet abrufbar.