best brute force method

Even if you crack Instagram accounts, they reset pass via email after first login, and you can't do nothing. Cracking Instagram accounts is good if you want to collect emails and numers

Using a dictionary password cracker would be good, with a good wordlist/rainbow tables, if you try brute forcing a long password, you would need a super computer and a bit of time on your hands. I do know on Windows you can get Cain and use that for password cracking, also John The Ripper is a good one too. I've used Kali before, if you aren't good with commands it's not the most user friendly, i'm pretty familiar with Linux so it's alright. John The Ripper is available for linux, so you would have luck with Kali in that perspective but Kali has some pre-installed password cracking tools. AGAIN to brute force gmail accounts or instagram accounts it takes a Hefty computer and a lot of time based on the length of the password.Also as shuttershades said, cracking the account does very little to benefit you cause once they see a different IP address the target will know you're trying to get in and stop it.

Nice explication...but there is another way. But for this you need some skills.
1.Find one Instagram/twitter/FB/etc account that has in the bio an website, (e-comerce,personal blog,etc/), if they also provide email in bio, much better.
2.We go to scamadviser.com and search info about domain owner, most of them did't use any protection so, you will see there full email and number phone.
3. We have an email...we go to the email log in page, we "forget" our pass so...we insert the victim email, then we will see the number phone number but only the first one or two digits and the last 2 digits, so we need to type the full number...that number that you found it on scamadviser.com
4. So the victim recive one link/temporary pass from one short number...
5. Now we need to move fast. We need one service online (you can find a lot) that can send and recive sms. You can send one sms with custom ID sender...so the victim it will recive an sms from "Facebook Security" or "Reset Confirmation" or blah blah blah
6.Now is time to use your brain and compose one sms, and make them to reply sms recive it from them to you...
Example:
"we need to confirm that you are the owner of this number..."
"for security reasons we need your full name and password recived"
etc etc

If you get acess to email account, you will get acess to social accounts...

Get SentryMBA, everything else is pointless.