Giveaway/Instagram

Yes, you can. From the guidelines

When posting links or content, that content should not force users, encourage users through reward, or primarily exist as a traffic source for users to perform an action for promotional, commercial, or monetary benefit. Such actions include but are not limited to clicking a referral link, liking a Facebook page, following a Twitter account, joining a Steam group, completing a survey, or making a donation. (Please note, in giveaway descriptions we do allow users and developers to link to their related Steam Greenlight, group, and store pages, as well as their social media channels. Users are also able to reference their group giveaways when posting in the Group Recruitment category of our forum.)

by promoting I will not be obliging someone to follow me, I will only be divulging. Is this allowed?

thx guys

I have to ask... why on earth would you want to do that?
(not bashing - asking - i dont understand).