To get the maximum Basic State Pension, you must have 35 qualifying years (which means you must have made National Insurance contributions for 35 years). So, your accountant means that you should pay yourself enough salary to make a National Insurance contribution – and get a “tick” towards the 35 “ticks” you need for a full Basic State Pension.
For the current tax year – 2019/20 – this would mean a salary of more than £6,136. Above this figure, you start paying National Insurance at (strangely enough) 0% – which counts as a qualifying year. At a salary level of £8,632, the Employee’s National Insurance rate increases to 12%. (Employer’s National insurance at 13.8% also begins at a salary level of £8,632).