In a stoich lab what is a change you could make to your experiment to bring the percent yield closer to 100%?

this is all we got for our procedure....you and your partner will react baking soda and a 1.0-M hydrochloric acid solution. You will then isolate the product, determine the purity/quality of your product, and determine the percent yield. you will then yze your original procedure and make adjustments that you think will change the percent yield in a favorable direction. the experiment will be performed a second time with the procedural changes and the percent yield will be recalculated. my partner and I have the first procedure done, but we don't know what to do to possible get a better percent yield. if you could help that'd be awesome!