To establish an enterprise taxation system, follow these steps:

1. Needs analysis: Understand the company's tax management situation and assess tax compliance risks.

2. Framework development: Define the system's name, scope, purpose, and legal basis.

3. Content formulation: Include internal tax management policies, financial reporting systems, and tax administration regulations.

4. Approval and release: After multi-department review and approval, publish through internal notices and training.

5. Implementation and supervision: Ensure execution via training, assessments, and incentives, while establishing oversight mechanisms to strengthen internal audits and risk control.

The corporate tax system refers to a set of internal regulations established by enterprises to standardize tax management and comply with laws and regulations. It includes two aspects: financial and tax management, aiming to ensure that the company's financial and tax activities meet national legal requirements, reduce tax risks, optimize tax costs, and maintain a good corporate image and reputation. The main components of the corporate tax system include:

1. Financial reporting system: Ensures that the company's financial reports are truthful, accurate, and complete, reflecting its financial status and operational performance.

2. Tax management system: Includes tax registration, calculation, declaration, and payment, ensuring the company fulfills its tax obligations legally and compliantly.

3. Internal tax management system: Standardizes the company's revenue and expenditure management, invoice management, expense reimbursement, contract management, and salary management to ensure all financial activities are lawful and compliant.

The impact of messy accounts on a company includes:

Tax risks: Chaotic accounts may lead to errors in tax reporting, increasing the company's tax risks.

Impact on decision-making: Financial data loses its reference value, misleading management decisions.

Tax audits: Messy accounts may result in false tax declarations or tax evasion, which could lead to fines or being blacklisted as a 'tax anomaly' if discovered.

The main reasons why companies end up with messy accounts include the following aspects:

Management and financial control issues: Chaotic business processes and procedures, lack of internal financial controls, disjointed financial roles with no checks and balances, failure to reconcile accounts, leading to isolated operations.

Human factors: Accounting staff may lack professional expertise, leading to irregular handling of accounts; frequent turnover of accounting personnel without proper handovers, resulting in account confusion.

Inadequate internal control systems: Poor internal management and incomplete control mechanisms, leading to unclear financial data.

Weak enforcement of financial systems: Poor implementation of financial policies, non-standardized accounting practices, causing account disorder.

Insufficient competence and professionalism of financial staff: Financial personnel may lack the necessary skills and professionalism to meet accounting requirements. Other departments or external partners may fail to cooperate adequately, leading to inaccurate financial data.