Step1
Memorize the endings. For verbs that end in -ar, the present-tense subjunctive endings are as follows: -e (yo), -es (tu), -e (el, ella, usted), -emos (nosotros), -eís (vosotros), -en (ellos, ellas, ustedes).
Step2
For regular -er and -ir verbs, the present tense subjunctive endings are as follows: a (yo), -es (tu), -e (el, ella, usted), -amos (nosotros), -aís (vosotros), -an (ellos, ellas, ustedes).
Step3
Memorize the spelling changes of -er verbs. The usual subjunctive endings apply, but the root portion of the verb changes for -er verbs that end in -cer (such as conocer, crecer). These verbs are conjugated according to their present-tense "yo" form, for example, reconozco--present-tense subjunctive: reconozca.
Step4
Memorize the spelling change for -ar verbs. -Ar verbs that end in -gar change to -gu (plus ending) in the subjunctive. For example: jugar, juegue.
Step5
For most irregular verbs, the subjunctive will follow the spelling change of the "yo" form in the present tense. For example, decir—present tense: yo digo; subjunctive: diga. Tener—present tense: yo tengo; subjunctive: tenga. Ver—present tense: veo; subjunctive: vea.
Step6
Use the subjunctive for negative commands. Affirmative command: "Habla." Negative command/subjunctive: "No hables."
Step7
Use the subjunctive to express wish, surprise, doubt, necessity. Wish: "Quiero que vengas manana" (I want you to come tomorrow). Surprise: "Me sorprendo de que me trates asi" (I’m surprised you're treating me this way). Doubt: "No creo que tenga buenas notas este semestre" (I don’t think he/she has good grades this semester). Necessity: "Necesito que me des la dirección de Chema" (I need you to give me Chema’s address).
Novice 
