Use давђй(те) + infinitive to express "let's" with Imperfective verbs.
Use давђй(те) + non-past to express "let's" with Perfective verbs.
This construction with давђйте 'let's' is a future expression, as it refers to a future event. In fact, it is possible to use forms of бІть + Imperfective infinitive in the давђйте construction (Давђйте бџдем говорќть о винќтельном падежљ 'Let's talk about the accusative case') just as you do to express future (МІ бџдем говорќть об ітом 'We will be talking about that'), but we will ignore that variant for the time being.
As for Perfective verbs, use the non-past in the давђйте construction (Давђйте поговорќм о другћм 'Let's talk about something else) just as you express future with the non-past (МІ поговорќм об ітом 'We will have a talk about that'). Use давђй instead of давђйте informally.
Давђй(те) читђть. (Impf.) Let's read.
Давђй(те) прочитђем (Pf.) іту статьє. Let's read this article.
You can omit the word давђйте with certain Perfective verbs (especially verbs of motion):
Пойдём в кинћ. Let's go to the movies.
Поговорќм о другћм. Let's talk about something else.