Marketers are tweeting on the wrong days, failing to include engagement-boosting hashtags and missing Twitter opportunities by not asking followers to retweet.

That’s according to a new study by Salesforce.com’s recently acquired Buddy Media, which analysed user engagement from more than 320 Twitter handles of the world's biggest brands.

According to the findings, Twitter engagement rates for brands are 17% higher on Saturday and Sunday compared to weekdays, but brands don’t take advantage of this trend and are wasting time posting on Wednesdays and Thursdays when engagement is lowest.

Instead, brands should tweet when engagement is highest for their industry even if this means on the weekend, as in the case of publishers and clothing retailers.

Meanwhile, the report warned that on days when activity is highest, tweets should still be kept to a minimum of four or less. Additionally, tweets that contain less than 100 characters receive 17% higher engagement than longer tweets and posts containing links receive 86% higher retweet rates than those without.

Tweets with hashtags receive two times more engagement than those without, said the report. However, only 24% of Tweets contain hashtags, meaning many brands are missing out on this opportunity to increase engagement.

Marketers specifically asking followers to ‘retweet’ or ‘RT’ receive 12 times higher retweet rates than those that do not use this call to action, according to the findings. But despite this, less than 1% of brands actually implement this.

Despite 77% of brands citing Twitter a top priority, Tami Dalley from Buddy Media claimed there’s room for improvement: “It’s great that brands are active on Twitter but it’s crucial they know best practices for publishing engaging content. Reach and engament can vary drastically with minor tweaks.”