You should post links and send people to interesting content and also should send them messages and follow them. Don't miss to promote your Twitter URL.
Try to increase your followers or else twit some more interest and important things. Then they might be following you. I found some sites there are sharing twitter like and plus like (twinds.com). Make more points and reduce it for what like you want. Give a try on that.
Have something worth talking about.
Without that your "followers" will simply be other "marketers" who are only interested in spamming you with their junk rather than you spamming them with your junk. Or they will be bots.
To get genuine followers, I suggest you to share interesting post on your both accounts and Put the twitter and Google plus icons on your website/blog if you have any.