Cannot Login White Screen of Death

I tried to add Headers & Footers plugin on my site so I could add Google Analytics.

With zero experience adding codes in, I definitely added the tracking ID to the wrong spot because now I get this when I try to go to my login page:

Warning: Cannot modify header information - headers already sent by (output started at /home/lipstickandcowboyboots/ in /home/lipstickandcowboyboots/ on line 1174

Anyone have a simple way to fix this?

SFTP to your server and delete that plugin folder.

I figured as much but…
I dont know how to SFTP
I dont have login to my site host (Dream Host) as I paid someone to design this blog site. Finally got in contact with her, but her back page guy is busy and hasn’t got back to me.