How should non-compete clauses be drafted and what should I consider?

You and your employer can agree on most things that are not regulated by law, but not under any circumstances. The agreement presented by your employer is usually called a competition agreement or non-competition clause, and there are a number of things you should consider before signing the agreement.
The starting point is that there is freedom of contract for what is not regulated by law, but if agreements are unreasonable, they can be adjusted by a court. However, this requires that a dispute arises where some wording in the contract or the contract is unfair. On the other hand, it is possible to have a dialog about the reasonableness based on the cases that have previously gone to court.
There are three things that determine whether the competition agreement is fair or not, and these are your position, the compensation you receive (during the time you are in quarantine, the period of time between when you left your old employer and before you started working for the new employer) and the length of time you have to be in quarantine. For example, if you work as a research manager at a pharmaceutical company, there is usually a risk that the employee could reveal information that could harm the old employer if they move to a competitor. In this case, a non-compete agreement may be reasonable, but a long period of time (quarantine) and a higher amount of damages may be required depending on the circumstances.
If you work as a salesperson instead, there may be less information that can cause damage. The products are still on the market and competitors can investigate the product themselves - there is not the same need for a non-compete agreement and the reasonableness can be questioned. In this way, your duties can guide the assessment of whether the non-compete agreement can be considered reasonable or not.
To summarize, you and your employer may agree on such agreements, but you must receive reasonable compensation during your quarantine period and your work duties may determine whether the agreement can be considered reasonable. In other words, you can sign such contracts but not just any contract.
Discuss with your employer what the non-compete agreement should protect in your position and also demand that your employer explains which companies can and cannot be considered competitors. That way you won't have to have that discussion if you intend to leave in the future.