From what I've heard, there is no limit on how many can follow you per day. The most you can follow per day is 1,000. Also, once an account is following 2,000 users, twitter starts limiting you on the additional users you can follow. They decide this on the ratio of followers to following. As far as I know, there is no published information on this ratio.
you can accept as many followers as you want, as much as I know you can't follow more than 1,000 users per day. Well if you are looking for more followers without worrying about limits, try joining social media exchange like http://keeko.com/
for new account maximum is 300 a day but for aged account I think it's ok to follow 1000 followers a day