You cannot appoint a clerk as a consultant.
Who is a consultant?
A consultant is someone who is consulted for advice. They will not be working for you alone, and their presence will not be required in your office from Monday to Saturday, from 9 am to 6 pm.
As advised by many members here, if you employ a person as a consultant and deduct 10% TDS from the "fees" paid to them, you will face charges from Income Tax, ESI, EPF, and many other labor departments. The Income Tax authorities will ask you what advice this clerk is giving you and on what basis they are attending your office regularly. In the case of Vs Wockhardt Hospital Ltd Vs Department of Income Tax, a similar question arose. The hospital was employing doctors as consultants and deducting TDS under section 194J, treating them as professionals. The Income Tax authorities found that these doctors were regularly employed and all the HR-related policies like leave rules, exclusiveness (not to work anywhere else), timing, etc., were applicable to them. It was found that these establish that they are not consultants but employees whose income should be subjected to deduction of income tax under section 192 as if they are paid salaries.
In your case, the EPF and ESI authorities will also demand contributions subject to coverage conditions relating to salary. They may demand it after several months, and by that time, the clerk you had appointed may have left the company, but you cannot escape from your liability; you should pay both the employee's contribution as well as your share of the contribution.
Therefore, even if your work is not regular but for a short period, you should not compromise on legal compliances. Appoint one person under a fixed-term contract for, say, one year or six months, paying them a 'salary' and deducting PF and ESI as applicable.