IF there were no contract, you could clean houses for your clients so long as *they* contacted you for it (you cannot use client information you only have from your employer to deliberately take their clients, but those clients can reach out to you). However, you indicate that you "signed a contract"; you need to have an attorney review the *exact* wording of the contract and discuss the situation with you to know whether you can clean for these clients or generally compete with your former employer. Non-competition and non-solicitation (don't "solict" or take customers) agreements are legal, but they are only enforced as per what they actually say, and they are not enforceable in all circumstances; that's why you need an attorney to review this with you.