Disclaimer: Most of my experience in this topic involves US-based institutions. While some parts may be universal, please check with your local funding agencies for specific instructions.
Funding is necessary for supporting any type of research. As a graduate student, securing funding for your own studies demonstrates initiative and a drive for independence. While many funding opportunities are competitive, there are multiple avenues open to researchers at various career stages. Finding these sources is a whole endeavor itself. Utilizing your network can help reveal potential places to apply and provide critical insight into the entire grant writing process. Where should you start? I have listed several sources down below that may offer guidance in your funding search.
Ask your Graduate Mentor. Funding is vital to run a lab, and your mentor has ample experience in applying for funding. At least in the US, the graduate funding application process is similar to that of senior investigators. Your mentor may provide valuable tips in your search. Their own network may reveal potential topics of interest that coincide with your project, which may increase your chances of receiving funding.
Ask fellow graduate students. Your colleagues may also be searching and applying for grants. Senior graduate students in your lab may know some helpful tips as: where to send applications and how to start the process. I have found being in a writing group with my fellow graduate students helpful, and provides a safe space for exchanging ideas. These sessions can be conducted virtually or in-person as frequently as you need. You can even join the PhD Balance Discord and see if other members are willing to join along.
Ask your graduate program/institution. Another resource that is available to graduate students is their graduate department. While graduate departments may differ from each institution, they exist to help maintain your graduate program. Internal funding through institutional or even departmental funding may be available to those who qualify. Your institution may also allow graduate students to access large funding databases, such as Pivot, opening access to more sources of funding.
Ask funding agencies. Government agencies, such as the National Institute of Health (NIH) and the National Science Foundations (NSF), are the main sources for research funding within the United States. One important person to contact is the program officer. This individual reviews prospective project proposals to identify promising research that aligns with the agency's overall vision. Talking to a project officer within your research field about your future grant application can provide valuable guidance on shaping your application. Depending on the funding agency, finding a program officer can be done through the agency's website. If in-person interactions are allowed, project officers often attend scientific conferences. They are willing to schedule a meeting to chat about projects.
Ask your scientific societies. Conferences usually are sponsored by scientific societies and offer travel grants to cover the overall costs such as lodging and registration. Scientific societies are organizations focused on furthering the understanding of a scientific topic, including the development of junior researchers. Therefore, these societies may offer developmental grants for graduate students in their discipline. Find a scientific society related to your research topic to consult.
Ask vendors! While this may sound strange at first, several scientific companies do offer funds in the form of travel grants to conferences. Since their primary consumers are researchers, investing a bit in their consumer base benefits them in the long run. Several companies may also offer grants that fund the costs to use their services based on what project adheres to their vision.
Funding is essential to science and therefore is very competitive to receive. There are many sources to receive funding, even from unconventional places. Grant writing will be a necessary skill as you move forward in your academic career. It demonstrates your ability to communicate your ideas and vision for your research.