1. Fixed-term savings plan: a part of salary is deposited in the bank fixed deposit every month to accumulate the down payment. Suppose Xiao Wang has started working now, and he can save 5,000 yuan every month and 300,000 yuan as a down payment in five years. It should be noted that banks or wealth management products with higher interest rates should be selected to improve the accumulation speed.

2. Investment and financial planning: If Xiao Wang has certain investment experience and is willing to take risks, he can also consider saving the down payment for buying a house through investment and financial management. Assuming that Xiao Wang chooses to invest 5,000 yuan a month with an annualized rate of return of 8%, he can accumulate to about 298,000 yuan in five years. It should be noted that risk control and rational allocation of assets should be paid attention to in the investment process.

In short, the specific choice of which scheme needs to be comprehensively considered according to Xiao Wang's own situation, and it needs careful planning and reasonable arrangement of his income and expenditure and time.