How do I conjugate regular verbs in the present tense?

First things first, we take the infinitive. Then, we take a look at the ending, or the last two letters. There are three groups- verbs ending in -er, verbs ending in -ir, and also verbs ending in -re. They conjugate slightly differently so it's important to determine which group we're dealing with. Then, we take off the -er, -ir or -re, and add specific endings that depend on the subject. With ER verbs, for example 'parler' (to talk), we would take off the -er, and then go through the conjugations. 'Je' adds an -e; 'tu' adds an es; 'il', 'elle' and 'on' add an -e; 'nous' adds -ons; 'vous' adds -ez; 'ils' and 'elles' add -ent (remember this -ent ending is silent when spoken). So 'I talk' would translate as 'Je parle'; 'we talk' would become 'nous parlons', and so on. It's the same principle with the two other groups: so with -IR verbs, for example finir (to finish), we would take off the -IR and add specific endings. 'Je' takes -is; 'tu' takes -is too; 'il', 'elle' and 'on' take -it; 'nous' takes -issons; 'vous' takes -issez; 'ils' and 'elles' take -issent (remember the -ent here is also silent). So, 'I finish' would be 'je finis', 'they (m) finish' would be 'ils finissent', etc etc. Finally, with the -RE groups, for example 'vendre' (to sell), we take off the -RE but add these endings instead. 'Je' takes s; 'tu' also takes s; 'il', 'elle' and 'on' don't take anything, so you just leave the ending blank so to speak; 'nous' takes -ons; 'vous' takes -ez; 'ils' and 'elles' take -ent (again, silent when spoken!). So 'I sell' would be 'je vends', but 'he sells' would be 'il vend'. Et voilà, you've conjugated regular verbs in the present tense!