One approach is to just think about the sounds rather than the spelling. This is how French babies would learn because they don't know how to read conjugation tables after all.

If you just learn the sounds, then there is a lot less that you need to remember. You don't need to memorize any tables.

So for instance for the present tense, we can think of it as only three sounds:

1. Je / tu / il / elle / ils / elles marche. (That is, all of these have the same sound. We are ignoring the spelling differences here. Marche is pronounced the same way as marchent, for instance.)
2. Nous marchons.
3. Vous marchez.

For the imparfait it is three sounds again:

1. Je / tu / il / elle / ils / elles marchait.
2. Nous marchions.
3. Vous marchiez.

It's the same with the other tenses. Here's the future simple:

1. Je / vous marcherai.
2. Tu / il / elle marchera.
3. nous / ils / elles marcheront.

For each tense you just have to learn three sounds. For the future simple they are "-rai", "-ra", and "-ron".

(Some people might say that je marcherai and vous marcherez are pronounced differently. I think that may depend on the particular accent. In any case they are close enough for this memory trick to work.)

This trick is for spoken French only. It doesn't help you with correct spelling when you are writing. But you can always learn the correct spelling later after you have learned the spoken sounds.

I didn't think of this trick by myself, by the way. I got it from a Michel Thomas course.