Cast Sensei's Divining Top either from your hand or from the top of your library by paying 1.
Alela triggers, creating a 1/1 Faerie creature token.
Activate Ashnod's Altar by sacrificing the Faerie, adding CC.
Activate Sensei's Divining Top's second ability by tapping it, causing you to draw a card and put Sensei's Divining Top on top of your library.
Repeat.
This elegant loop lets you draw your entire deck and generate a massive surplus of colorless mana by turning a humble artifact into a self-sustaining engine. Madame Web, Clairvoyant provides the crucial top-deck casting permission that allows Sensei's Divining Top to be repeatedly played directly from your library, while Alela, Artful Provocateur uses those artifact casts to continuously manufacture fresh 1/1 Faerie creature tokens. You then feed those tokens directly into Ashnod's Altar to recoup the mana needed to recast the Top, drawing a card each cycle as Sensei's Divining Top taps and tucks itself away before the process begins anew.