Write a business plan, darn it! :)
So many entrepreneurs just "wing it". Unless you're a genius, it's not possible to improvise in business because even when you DO succeed, the infrastructure or plan is not in place to maximize your return on that accidental success!
Sure, writing a solid business plan is hard work. But the good news is, it almost enables you to win BEFORE you play the game of business (too many entrepreneurs try to play the game and struggle to win. It's the reverse: win on paper first, then play it out in real life.
Be disciplined with gathering, interpreting, and making decisions based on data. too many entrepreneurs run their businesses completely on intuition, whereas a nice balance should be struck between intuition and what data is telling us.
Easily overlooked, my best advice is to brush up on your people skills.
You started your business because you wanted to do what you love and enjoy financial and daily freedom. Living the dream... so It's a pretty rude surprise then when new clients are as demanding as the boss you left behind.
Decide how you do your best work- payment, deadlines, revisions, decision-making- then use your people skills to have an onboarding conversation with your clients. Teach them how to treat you so they get the results they want (and you get to stress less & be well-paid)
Speak your truth about what you want in your work life to yourself and your clients. You owe it to yourself and them.
These are all great answers and all critical for business success.
Being, and staying, incredibly focused on who you are (brand), who you serve (be VERY specific here) and how you serve them are critical. Don't get distracted with all the amazing new ideas that come to you each day. Write them down somewhere and refer back to them when you have time. Only act on them if they're in line with who you are, who you serve and how you serve them.
Another area where I see entrepreneurs stumble is in building and utilizing a core team. So many entrepreneurs think they can do it all themselves, don't know how or want to delegate, are afraid of getting screwed (bad past experience) or simply don't think that anyone else can do things as well as they can. This will stifle the launch and growth of any company.
Create a great team where one person's strengths make up for another person's weaknesses. Let everyone do what they're best at while coordinating all actions and making sure that everyone shares similar values and knows what the common goals are.
As an entrepreneur, if your business is hitting a glass ceiling of revenues at a certain level and can't seem to budge, the issue is that the leader's growth as a person has stagnated and it's time for new influences (new team members or advisors who know what it takes to move the company forward). I've mentored owners to move them from "mom & pop" thinking to "growth business" thinking. It's not always easy but it's usually necessary to move the company forward.
Don't worry so much about making right decisions. Make decisions. Then make them right.
It's similar to Simon's advice.
I'd also like to add to Kathrin's excellent advice: Show up [and improve a little] every day.
The one thing? Haha. But sure, the one thing: Show up every day.
I coach solopreneurs to develop their businesses and hard work/persistence seems to be the number one differentiator. Of course, a passion, a real idea, a great product, a strategy, etc. they are all part of it. None of it will ever come to existence without YOU doing things every day. Or every day of your four-day-work-week. :)
Always keep an eye on your cash flow. Most new business that fail do so because they run out of cash. Beyond passion and commitment, you need enough cash to get through the rough times at the beginning. And find a trusted advisor that can help you with this.
Perfection and success are a journey, not a destination, so be prepared to fail and determined not to waste what those failures teach you about both yourself and the way you have done things.
In business, failure usually comes with a painful price tag - those who learn, persevere and prevail, see it as an investment and a valuable learning opportunity. Those who give up, don't even want to think about it, or worse - they avoid the learning opportunity altogether and place the blame on others.
Have clear goals, create your game plan, execute, and track (business metrics). All successful people have goals, an game plan they execute and track their activities/ results.
You are the the Top Sales Person for your company, don't separate yourself from your customers, they are the most important part of your business....take time to engage.