The main advantage of the Spanish language is that it is pronounced just as it is read. Therefore, the first step is to learn the alphabet in Spanish, which you may do using learning websites online that come with listening exercises. Once you master this step, any word you read from your dictionary and which you use when speaking Spanish, will be most likely pronounced correctly, and Spanish speakers will understand you.
Learning the rules of basic verb conjugations (simple past, present and future) will allow you to form real sentences. Even if you have to look up the words and nouns to form simple sentences, you will already know the basic conjugation rules and therefore be able to utter sentences such as: "Quiero ir al baño" (I want to go to the bathroom), "Una cerveza por favor" (One beer please), "Mañana iré a la playa" (Tomorrow I will go to the beach) or "Ayer comí con mis amigos" (Yesterday I ate with my friends).
Definite and indefinite articles, as well as gender, are the basics of the Spanish language, and must be learned in order to speak correctly when using a dictionary. The good thing is that when using the dictionary to look up a word in Spanish, it will already tell you if it is feminine or masculine. So all you will have to remember are the rules for using the definite and indefinite articles. When in English we use "the" as a definite article, in Spanish there are four forms:
el: masculine singular (ex. the cat, el gato)
la: feminine singular (ex. the cat, la gata)
los: masculine plural (ex. the cats, los gatos)
las: feminine plural (ex. the cats, las gatas)
Notice how the definite article used affects the ending of nouns in Spanish.
The indefinite articles in English are: a, an and some. In Spanish, there are four:
un gato: a male cat
unos gatos: some male cats
una gata: a female cat
unas gatas: some female cats
Again, notice how the use of the indefinite article in Spanish changes the endings of the nouns.
Once you mastered the basics of Spanish grammar and pronunciation, you will be ready to start using the dictionary to speak Spanish correctly. Since you will know the rules, now you can take your time and look up the words and verbs you need in a dictionary and form your sentences in Spanish.