How to Increase Standards of Living
The best way is to subsidize the building until the cash reserves pools up. You have to change your laws around to allow you to subsidize certain jobs. Ideally you want to click on buildings tab zoom in to your state. Click on your state and check the level of employment. If it is not filling up, the easiest way is to introduce a law to subsidize the less popular job.
Population usually also is an issue, so make sure they are not just working a different job instead because you have too many buildings.
Lowering the cost of what pops need the most will increase their sol. Food and clothing seems to be main thing but you can check by digging into the population tooltips from the top bar. Also make sure they are mostly all employed so they have money to spend on things. Lowering taxes too helps of course.
Wages will mostly depend on the actual businesses doing well. So if a business is making more profit it can pay better wages to all of it’s workers. Skilled workers will always make more but it’s relative so all workers in the building will still benefit and so they all get improved wages over what they expect as a minimum. If the building is not doing well wages might suffer and they might even start firing staff.
As long as their is high demand for what they are producing it should be fine but at some point you might cross a threshold of over supply and then they might start losing money. Also bear in mind how improving buildings affects the working population. Sometimes upgrading to a better production method will be good for the business but it could mean a lot of labourers are let go whilst more engineers are hired. So that might be bad for lower class wages/sol but maybe only temporary if other vacancies exist. I like to check on peasents and unemployment numbers when building or upgrading buildings. Sometimes I might even downgrade a building so they hire on more labourers. It’s a bit of balancing act and all depends on how your current situation is.