Social media marketing holds a special allure for startups. It is the best vehicle, ever, for propelling your new business forward fast and gaining momentum you can build on. However, social media has to be done right. To execute properly, you have to begin strong, know what to do and what to avoid.

Related: 12 Social Media Mistakes That Entrepreneurs Make

As a newcomer, you get only one chance to make a good first impression with folks on social media. If you lose that chance you’re going to fall behind and stragglers have to work twice as hard to cover lost ground on social sites. So know these cardinal sins that you must never commit, because if you do then it’s a quick descent to the purgatory of social media irrelevance.

1. You don’t have to be everywhere. Yes, the temptation is strong. The perception is every social media site is a fertile hunting ground for prospects and if you don't get them, somebody else will. 

It is not easy to come up with original and relevant content for many different social networks. It results in a poor foundation for the whole social media marketing process. For starters, only choose the networks that have the most targeted prospects and the largest audiences. As you expand sales and build your team, you can experiment with other networks but, out of the gate, you must focus on quality over quantity.

2. Don’t be that guy. Extensive promotions without audience engagement is akin to social media suicide. Self-promotion is fine but finer still is a balance between interesting content and engagement, on one hand, and marketing on the other. Follow the 80/20 rule. Getting the balance wrong has put many a startup on the one-way road to social media oblivion. Creative marketing will get you audience and accolades. Old-fashioned one-way advertising derived from an offline marketing mindset will only hurt your business.

Related: Brian Solis on Five Common Social Media Mistakes and How to Avoid Them

3. Failing to plan is planning to fail. If people don’t trust you or know about you, it won’t matter how great your product or service is. Stop expecting to go viral and have people flock to your business by the thousands unless you create a buzz and let people know you’re there.

Cross-pollination of content, quizzes, polls and videos will help, but you need to establish a posting schedule and follow it. Your audience will get used to your presence and know that you engage. Your objective might be be leads, brand recognition or sales but plan with it in mind.

Clear objectives simplify planning and execution, as well as enabling you to measure results and track ROI. Hope is not a strategy, not with social media or any other form of marketing. 

4. Boring content is counterproductive. Talk with the audience, don’t talk to them. Don’t barge into timelines with dull opening lines. Make an impressive entry with humor, an intelligent response, a genuine question, etc. Infuse your personality into your posts.

Crack these and you’re on your way to selling without selling.Your objective is to attract eyeballs and stimulate engagement, so don't bore people. Be careful that you are not turning people off without even knowing that you are doing it. 

5. Stay enthusiastic. Many startups have lost steam after a strong start, sometimes out of laziness and lack of focus but very often because of impatience. A social media program is more a marathon than a sprint. Tweak performance by measuring metrics, tracking competition and adapting to what your audience is telling you with their behavior. If  your enthusiasm fades, the momentum wil tail off. 

Know your audience and be prepared to put in effort. Not everyone has a natural wit with a flair for language. Work on these things. There is every chance you’ll find yourself coming up with cool stuff that shows your audience you care. It’s an enjoyable thing to do. Enjoy it. 

Related: How to Correct 3 Major Social-Media Blunders