Configure your computer to allow you to type in Hebrew. Add Hebrew as a language in your keyboard settings.
Visit a website that will give you a guiding image of where each Hebrew letter is on a traditional American keyboard. Websites like 2Keystrokes.com and Linguanaut.com have big images of these keyboards for you to use as a guide.
Visit a superior online Hebrew-English dictionary. Websites such as Morfix(morfix.mako.co.il), Zooloo(zooloo.co.il/calc/edic) or My Hebrew Dictionary(words.co.il) have superior databases.
Use your guide to type in the word. Hit the "return" key. Write down all possible definitions.
Consult an expert in the field to which your word is connected for an interpretation; ideally, someone who speaks Hebrew. For example, if the word is biblical, ask a rabbi, if possible. If the word has to do with cooking, ask a cook who speaks Hebrew. This will give you a broader and clearer understanding.