That depends on whether or not you wish to defend the matter. If you do wish to defend the matter, you need to have valid lawful defence to the claim. Not every personal defence is a valid legal defence. If you do have a valid defence, you may file a Notice of Intention to Defend with the attorney who issued the summons and with the Clerk of the Court. The jurisdiction of the court will be indicated on the summons and you will have to file with the corresponding clerk.
This notice must be filed within the time period stated on the summons and there will also be a section on the summons itself where you may indicate your intention to defend the matter. If you have received a summons for a claim that you acknowledge, but are unable to pay the full outstanding balance, it is advised that you contact the attorneys who issued the summons in order to make payment arrangements.
Should you fail to do so, the attorneys may proceed with judgment and follow the ordinary collection procedure, which will cost you more in legal fees.