Security of the citizens
It is a primary job of every government to maintain law and order in the state. Protecting the lives of masses has to be the main priority in the preamble for general welfare. Without ensuring its citizens adequate life security, no government can claim to be working for the welfare of its citizens.
When a preamble mentions general welfare, it includes basic health facilities in its sphere. It is a job of a government to provide medical facilities to the masses, which should be in the reach of even the poorest. In countries, which claim to be welfare states, medicines and health facilities are absolutely free.
No nation in the modern world can move towards the right direction without putting emphases on education. Schools, colleges and universities are a crucial component of the general welfare of the citizens of anystate. If only a certain class of a society is able to get quality education, then your country is surely not going in the right direction.
A government, which is concerned about the general welfare of the masses, has to adopt such policies that a common man can easily find employment and feed his family. Those employment opportunities should be according to the potential and education of an individual.
Without having a proper infrastructure, no government can provide comfort to its citizens. In the current era, communication and transportable infrastructure are the backbone of development in a country.