I started playing guitar 3 months ago. Few days ago I realized that I played only downstrokes. Should I learn upstrokes to play faster?
I'm thinking of playing one month only upstrokes, and after I would try to play Downstroke-Upstroke-Downstroke-Upstroke all the time. Is that good? And also, I realized that I don't use my pinky finger so much. Should I play with my pinky finger?
In a word, yes. You need upstrokes to get faster. Not sure if this will work for you, it worked for me, but, find a long legato piece that you like (I used the one from Surfing with the Alien) learn it. Then, alternate pick(up/down/up/down) the whole thing. Maybe try economy picking, I use it, it's fast enough for what I play(Hard Rock, Hair Metal)

About the pinky finger thing, I read somewhere that Jimmy Page doesn't use his pinky finger that much too. I only use my pinky if I need to reach up 5+ frets.
This should've been posted in the Guitar Techniques subforum.
You'd get better help there.

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Alternate picking is pretty important, just take the pentatonic scale and play it using down/up/down/up etc...

Some people use the pinky a lot some never, i use it for stretches and when playing in the middle of the neck i like to have 1 finger per fret but i'm not that consistent with it, i do what i feel at the time, just use your pinky a bit to build up strength and eventually you'll decide how much you use it
"Music Without Emotion Is Like Food Without Flavour"
Paul Gilbert
Absolutely. Alternate picking can be very useful. And pretty necessary for playing at higher speeds. As for your pinky, start using it. Some guitarists don't use it as often as they should, but the way I see it, if you have it, why not use it?
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Junior's usually at least a little terse, but he knows his stuff. I've always read his posts in a grouchy grandfather voice, a grouchy grandfather with a huge stiffy for alternate picking.
Besides that, he's right this time. As usual.
Yeah just start getting into the habit of playing everything up and down instead of just downstrokes.
Actually called Mark!

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