First and foremost, when and if you come across a yeast infection, contact your healthcare provider. They will recommend you with over-the-counter (OTC) vaginal creams or suppositories that have miconazole or clotrimazole in them. Also, you must avoid the intake of oral fluconazole tablets to treat a yeast infection during pregnancy.
As for what you could do, try keeping the vagina dry, wear cotton panties for air circulation, reduce the intake of sugar, etc. To know of more remedies, read the content above.