Rescind Article 50. This relieves the time pressure upon the decision making process and means that decisions can be made in a calm, reflected manner, not in a panicked state. It also prevents the threat of No Deal / No Brexit being used to blackmail any decision.
Pass a law to force all MPs to put their shares into a blind trust that can only be used invested in the UK. This will ensure that whatever decisions occur are free(r) from vested interests. If a decision is ultimately good for the UK stocks and shares will rise, if a decision leads the UK to economic ruin, those responsible will also take a hit. (You can call this law the "Put your money where your mouth is" law, if you like.)
Make your bloody mind up about what you can all agree upon. This may involve additional public consultations, referendums and/or general elections.
Once you've decided what you're actually going to back, if the decision is still to Leave, invoke Article 50 and do it properly this time. You may need to collaborate with members from other parties.
Regardless of the decision taken, visit the areas of the country where the opposite decision was chosen. This may highlight underlying social issues such as poverty and immigration. Where scientific evidence proves such social issues exist, implement measures to address them.