docs: update readme

and add reference to secp256k1 script

README.md

@@ -1,2 +1,22 @@
 # `BIP48`
-BIP-0048 "Multi-Script Hierarchy for Multi-Sig Wallets" for Dart.
+BIP-0048 "Multi-Script Hierarchy for Multi-Sig Wallets" for Dart.
+
+Used to derive "shared accounts" from Hierarchical Deterministic (HD) wallets.
+
+## Getting started
+```bash
+git clone https://github.com/ManyMath/bip48
+cd bip48
+dart pub get
+dart run coinlib:build_linux
+# Refer to 
+# https://github.com/peercoin/coinlib/tree/master/coinlib#installation-and-usage 
+# for build instructions for your platform.  Basically, use 
+# `dart run coinlib:build_platform` (select from: `linux`, `macos`, `windows`, 
+# `windows_crosscompile`, or `wsl`).  If these don't work, check for build 
+# scripts for your platform in the `scripts` folder.
+dart test
+```
+
+## Usage
+See the example and tests for usage.

scripts/linux/build_secp256k1.sh

@@ -1,6 +1,8 @@
 # This script is provided in case `dart run coinlib:build_linux` fails.
 #
-# Adapted from Stack Wallet's secp256k1 build script.
+# Adapted from Stack Wallet's secp256k1 build script. See
+# https://github.com/cypherstack/stack_wallet/tree/staging/scripts for scripts for additional
+# platforms.
 
 mkdir -p build
 cd build