Well, its very easy because it barely has any variations, for every verbs, for any kinds, you use
"ais" "ais" "ait" "ions" "iez" "aient"
Exemple:
-I had a cat when i was younger. - "J'avAIS un chat lorsque j'étAIS plus jeune."
-You used to like that. - Tu aimAIS cela.
-He/she was a chill guy. - Il/elle étAIT un mec sympa.
COOL THING: He/she don't matter in past tense
-We were naive. - Nous étIONS naïfs.
-You were doing some shopping. - Vous faisIEZ du shopping.
-They were funny to watch. - Ils/Elles étAIENT amusants à regarder.
These are exemples where i kinda overused some verbs, but its basically the same with any verbs.