You can start anytime as long as you have the resources,exclude signature campaigns so that you wont need to have high ranking accounts here to start earning.You can join social media boutny campaigns that will only require you to share,retweet posts of the ICO's social media account using your facebook or twitter accounts,translations will require you to translate either an ANN thread,bounty thread,or whitepaper and you will earn after the ICO has finally over.