Free Guides

Guides for Excel, AI Prompting, and Code

Short, practical explanations of the concepts behind every exercise on PractiseSkills — read the guide, then go practice it for real.

Excel Formulas

From basic arithmetic to nested lookups — 9 guides covering every category of Excel formula.

Fundamentals

Basic Excel Formulas for Beginners

Addition, subtraction, and why cell references matter.
Math & Rounding

SUM, ROUND & Math Formulas

SUM, ROUND, ROUNDUP, ROUNDDOWN, ABS, and MOD.
Counting & Averaging

COUNT, COUNTIF & AVERAGE

COUNT vs. COUNTA vs. COUNTIF, and AVERAGEIF.
Conditional Logic

IF, AND, OR & Nested IF

From a basic IF to IFS and multi-condition logic.
Conditional Aggregation

SUMIF and SUMIFS

Sum a range based on one or more conditions.
Lookups

VLOOKUP vs. XLOOKUP

Which lookup formula to use, and why.
Text Functions

LEFT, RIGHT, TRIM, PROPER

Cleaning and reshaping messy spreadsheet data.
Ranking & Statistics

RANK, LARGE, SMALL

Finding rank, and the top or bottom N values.
Combining Techniques

Nested Excel Formulas

Combining functions to solve harder problems.

AI Prompting

How to get better answers out of Claude and other AI models.

Fundamentals

How to Write Better AI Prompts

Task, audience, and format — what every good prompt needs.

Code: HTML, Python & VBA

Hands-on basics for three practical languages.

HTML

HTML Basics: Your First Tags

Headings, links, and form inputs, explained.
Python

print(), Loops & Functions

The three building blocks of most Python programs.
VBA

Excel VBA Macros for Beginners

Sub procedures, MsgBox, loops, and cell references.