ACAS and GOV.UK provide reliable online guidance on employment rights, tribunal procedures and time limits. In many cases, you must contact ACAS for Early Conciliation before submitting a claim, and the usual deadline may be as short as three months less one day, although the calculation depends on the circumstances. Keep relevant documents, such as your contract, payslips and correspondence with your employer. For advice on the strength of your case or how to prepare, consider speaking to a solicitor regulated by the SRA or a recognised employment advice service.