It (advertisement) serves directly to assist a rapid distribution of goods at reasonable price, thereby establishing a firm home market and so making it possible to provide for export at competitive prices.

　　第一步：断句子

　　[1] It (advertisement) serves directly to assist a rapid distribution of goods at reasonable price,

　　[2] thereby establishing a firm home market

　　[3] and so making it possible to provide for export at competitive prices.

　　[2][3]虽然没有谓语动词不是分句，但由于它们过于冗长，断开便于解析

　　第二步：串难点

　　[1] It (advertisement)主语部分serves directly to assist谓语部分a rapid distribution of goods at reasonable price宾语部分,

　　本句谓语动词词组serves directly to assist=directly assist;宾语部分a rapid distribution of goods at reasonable price中的抽象名词distribution语义上具有动词意味，可将其译为“将货物以合理的价格分销出去”;[1]理解为“广告直接帮助货物以合理的价格被分销出去”;或译意为“广告对以合理的价格分销货物有直接的帮助作用”

　　[2] thereby establishing a firm home market

　　thereby意为“因此”，是一个副词，不能连接从句，其后是一个分词短语做结果状语;establishing a firm market意为“建立一个稳固的国内市场”

　　[3] and so making it possible to provide for export at competitive prices.

　　[3]与[2]是并列关系，其中it是形式宾语，真正的宾语是to provide for export at competitive prices，making it possible是典型的“动+宾+宾补”结构，理解为“使得以具有竞争力的价格提供出口成为可能”

　　第三步：变语序

　　[1] It (advertisement) serves directly to assist a rapid distribution of goods at reasonable price,

　　[2] thereby establishing a firm home market

　　[3] and so making it possible to provide for export at competitive prices.

　　语序上本句一下两点需要做出调整，才更符合汉语习惯：

　　[1] [at reasonable price]状 +a rapid distribution译为动 +of goods译为宾

　　[3] making动 +to provide for export at competitive prices宾 +possible宾补

　　基本译文

　　它(广告)能够直接帮助货物以比较合理的价格被迅速分销出去，因此可以(使公司)建立一个稳固的国内市场，同时也使其以具有竞争力的价格提供出口成为可能。