Every business is different, but there are probably between 10 and 15 numbers that you can track regularly that would allow you to see at a glance if you're heading in the right direction.
Think about tracking both input measures (e.g. marketing spend or meetings arranged) and output measures (e.g. new clients or revenue). Your scorecard isn't for managing your whole business, just allowing you to focus on where you want to be and enable you to deliver your plan.
If you set targets properly so that they mean something then once you've tracked the numbers for a while you'll be able to see patterns and trends and even start to be able to predict the future.
"If you can't read the scoreboard you don't know the score. If you don't know the score you can't tell the winners from the losers"
see instantly whether you're above or below target with red and green automatic formatting
compare to the previous week and over
rolling 13 weeks
track up to 15 metrics weekly with adjustable targets
easy to use google sheet or EXCEL SPREADSHEET
choose 3 of your metrics that represent your sales funnel and see the conversion rates at each stage
select metrics to chart on a separate dashboard