Of your own accord
Definition 1 of 1
Pro Tip 1/3Self-initiative
Implies you're taking action on your own, without prompting from others. 
She decided to clean up the park of her own accord.
Pro Tip 2/3Positive Autonomy
Often shows positive personal qualities like responsibility or independence. 
He studied extra materials of his own accord to excel in class.
Pro Tip 3/3Unprompted Action
Indicates doing something without external influence or a direct request. 
She offered help of her own accord, surprising everyone.