Many Christians do not understand the difference between a calling and paid employment. A calling is what God created you to do. It is what will make a permanent difference in the world. Paid employment is what you do to support yourself and your family.
A few Christians are able to get paid employment doing their calling, but that is not normal. People called to be pastors can often get paid employment doing pastoral work (many are actually doing management or administration). A person called to be a prophet is unlikely to get paid employment doing their calling. That is why so many become pastors, which is a pain for everyone.
Paul was called to be a apostle, but that did not pay well, so he often took paid employment as a tentmaker. This will be the situation for most Christians. They will not be able to get someone to pay them to do their calling, so they will need paid employment in field where they have skills to earn a living, so they can carry out their calling. They should seek paid employment in a role where the can earn enough to live on as quickly as possible. This task may not be fulfilling and it may not have much eternal significance (all Paul's tents have rotted away), but that does not matter, if it leaves lots of time for the real calling.
I am called to Christian economics. I have never seen a job advert for a Christian economist, so I cannot support my family doing my calling. I have found employment in a role that has very little eternal significance, but it allows me to earn a living in three days a week, which gives me plenty of time to fulfil my calling.
Sometimes our employment will quite different from the calling. Making tents has very little to do with apostleship. Some people with more intellectual callings may need to do physical work to support themselves, but it will still pays better than stitching stinking skins into tents.
Christians should choose employment that will give their freedom to do their calling. Paul could have earned more money working as a lawyer for the Roman Empire, but it would have limited his freedom to be an apostle. Academia my provide employment for those with intellectual callings, but it can also limit their freedom to follow their dreams. I chose not to get employment as an economist with a secular institution, as that would compromise or confuse my freedom to publicise a Christian view of economics.
Christians should be salt and light whether they are exercising their calling or working in paid employment. They should choose their employers carefully, because they are required to submit to the authority of their employer. If the employer is not a Christian, he may not allow an employee to share the gospel during work time. That is not unreasonable, so a Christian in this situation will have to cover some of their light under a bushel. That does not matter, if it is shining clearly in other activities where they are free to manifest their calling is. Employers that force their employees to do things that are contrary to the gospel should be avoided.
Knowing your calling is really important. Too many Christians have only ever looked for paid employment and just assume that their employment is their calling. They are frustrated, because they are not fulfilling their calling.
If your calling does not pay, finding paid employment is quite liberating. Some Christians leave their calling on hold while dreaming of a rich benefactor who will fund them to exercise their calling. This is a vain hope. No one will understand the value of calling as much as the person called. If they get paid employment, they can be the benefactor for their own calling. They are freed from dependence on trite promises that God will provide.
Understanding that your employment frees you to fulfil your calling will quell the frustration at what can sometimes seem to be pointless effort. Hard work flies by, if you know that it will support you to do something of value