Provide evidence to prove the existence of labor relations, and then report or prosecute to the labor inspection brigade. It is illegal not to sign a labor contract, and salary deduction is even more illegal.
 According to Article 10 of the Labor Contract Law, a written labor contract shall be concluded when establishing a labor relationship. If a labor relationship has been established but a written labor contract has not been concluded at the same time, a written labor contract shall be concluded within one month from the date of employment. If an employer and a worker conclude a labor contract before employment, the labor relationship shall be established from the date of employment.
 Article 50 of the Labor Law stipulates that wages shall be paid monthly to workers themselves in monetary form. Workers' wages shall not be deducted or delayed without reason. Article 77 In case of a labor dispute between an employer and a worker, the parties concerned may apply for mediation, arbitration, bring a lawsuit or settle it through consultation according to law. The principle of mediation applies to arbitration and litigation procedures. Article 79 After a labour dispute occurs, the parties concerned may apply to the labour dispute mediation committee of their unit for mediation; If mediation fails and one party requests arbitration, it may apply to the labor dispute arbitration committee for arbitration. One party may also directly apply to the labor dispute arbitration committee for arbitration. If they are not satisfied with the arbitration award, they may bring a lawsuit to the people's court.
 According to Article 84 of the Labor Contract Law, if an employer, in violation of the provisions of this Law, distrains a worker's resident identity card and other certificates, the labor administrative department shall order it to return the worker himself within a time limit and impose a penalty in accordance with relevant laws and regulations. If an employing unit, in violation of the provisions of this Law, collects property from a worker in the name of guaranty or otherwise, the labor administrative department shall order it to return the property to the worker within a time limit, and impose a fine of not less than 500 yuan but not more than 2000 yuan per person; If it causes damage to workers, it shall be liable for compensation. If a worker cancels or terminates his labor contract according to law, and the employer distrains the worker's files or other articles, it shall be punished in accordance with the provisions of the preceding paragraph.
 To sum up, do you know what the boss should do without signing a labor contract!